Encoding.GetChars Encoding.GetChars Encoding.GetChars Encoding.GetChars Method

Definición

Cuando se reemplaza en una clase derivada, descodifica una secuencia de bytes en un juego de caracteres. When overridden in a derived class, decodes a sequence of bytes into a set of characters.

Sobrecargas

GetChars(Byte[], Int32, Int32, Char[], Int32) GetChars(Byte[], Int32, Int32, Char[], Int32) GetChars(Byte[], Int32, Int32, Char[], Int32) GetChars(Byte[], Int32, Int32, Char[], Int32)

Cuando se reemplaza en una clase derivada, descodifica una secuencia de bytes de la matriz de bytes especificada en la matriz de caracteres especificada. When overridden in a derived class, decodes a sequence of bytes from the specified byte array into the specified character array.

GetChars(Byte*, Int32, Char*, Int32) GetChars(Byte*, Int32, Char*, Int32) GetChars(Byte*, Int32, Char*, Int32)

Cuando se reemplaza en una clase derivada, descodifica una secuencia de bytes a partir del puntero de bytes especificado en un juego de caracteres que se almacenan a partir del puntero de caracteres especificado. When overridden in a derived class, decodes a sequence of bytes starting at the specified byte pointer into a set of characters that are stored starting at the specified character pointer.

GetChars(ReadOnlySpan<Byte>, Span<Char>) GetChars(ReadOnlySpan<Byte>, Span<Char>) GetChars(ReadOnlySpan<Byte>, Span<Char>) GetChars(ReadOnlySpan<Byte>, Span<Char>)
GetChars(Byte[]) GetChars(Byte[]) GetChars(Byte[]) GetChars(Byte[])

Cuando se reemplaza en una clase derivada, descodifica todos los bytes de la matriz de bytes especificada en un juego de caracteres. When overridden in a derived class, decodes all the bytes in the specified byte array into a set of characters.

GetChars(Byte[], Int32, Int32) GetChars(Byte[], Int32, Int32) GetChars(Byte[], Int32, Int32) GetChars(Byte[], Int32, Int32)

Cuando se reemplaza en una clase derivada, descodifica una secuencia de bytes de la matriz de bytes especificada en un juego de caracteres. When overridden in a derived class, decodes a sequence of bytes from the specified byte array into a set of characters.

GetChars(Byte[], Int32, Int32, Char[], Int32) GetChars(Byte[], Int32, Int32, Char[], Int32) GetChars(Byte[], Int32, Int32, Char[], Int32) GetChars(Byte[], Int32, Int32, Char[], Int32)

Cuando se reemplaza en una clase derivada, descodifica una secuencia de bytes de la matriz de bytes especificada en la matriz de caracteres especificada. When overridden in a derived class, decodes a sequence of bytes from the specified byte array into the specified character array.

public:
 abstract int GetChars(cli::array <System::Byte> ^ bytes, int byteIndex, int byteCount, cli::array <char> ^ chars, int charIndex);
public abstract int GetChars (byte[] bytes, int byteIndex, int byteCount, char[] chars, int charIndex);
abstract member GetChars : byte[] * int * int * char[] * int -> int
Public MustOverride Function GetChars (bytes As Byte(), byteIndex As Integer, byteCount As Integer, chars As Char(), charIndex As Integer) As Integer

Parámetros

bytes
Byte[]

Matriz de bytes que contiene la secuencia de bytes que se va a descodificar. The byte array containing the sequence of bytes to decode.

byteIndex
Int32 Int32 Int32 Int32

Índice del primer byte que se va a descodificar. The index of the first byte to decode.

byteCount
Int32 Int32 Int32 Int32

Número de bytes que se van a descodificar. The number of bytes to decode.

chars
Char[]

Matriz de caracteres que contendrá el juego de caracteres resultante. The character array to contain the resulting set of characters.

charIndex
Int32 Int32 Int32 Int32

Índice en el que se inicia la escritura del juego de caracteres resultante. The index at which to start writing the resulting set of characters.

Devoluciones

Número real de caracteres escritos en chars. The actual number of characters written into chars.

Excepciones

El valor de bytes es null. bytes is null. O bien -or- El valor de chars es null. chars is null.

El valor de byteIndex, byteCount o charIndex es menor que cero. byteIndex or byteCount or charIndex is less than zero. O bien -or- byteindex y byteCount no denotan un intervalo válido en bytes. byteindex and byteCount do not denote a valid range in bytes. O bien -or- charIndex no es un índice válido para chars. charIndex is not a valid index in chars.

chars no tiene suficiente capacidad desde charIndex hasta el final de la matriz para aloja los caracteres resultantes. chars does not have enough capacity from charIndex to the end of the array to accommodate the resulting characters.

Se ha producido una acción de reserva (vea Codificación de caracteres de .NET para obtener una explicación completa) A fallback occurred (see Character Encoding in .NET for complete explanation) - y - -and- El valor de DecoderFallback está establecido en DecoderExceptionFallback. DecoderFallback is set to DecoderExceptionFallback.

Ejemplos

El ejemplo siguiente convierte una cadena de una codificación a otra.The following example converts a string from one encoding to another.

using namespace System;
using namespace System::Text;

int main()
{
   String^ unicodeString = "This string contains the unicode character Pi (\u03a0)";
   
   // Create two different encodings.
   Encoding^ ascii = Encoding::ASCII;
   Encoding^ unicode = Encoding::Unicode;
   
   // Convert the string into a byte array.
   array<Byte>^unicodeBytes = unicode->GetBytes( unicodeString );
   
   // Perform the conversion from one encoding to the other.
   array<Byte>^asciiBytes = Encoding::Convert( unicode, ascii, unicodeBytes );
   
   // Convert the new Byte into[] a char and[] then into a string.
   array<Char>^asciiChars = gcnew array<Char>(ascii->GetCharCount( asciiBytes, 0, asciiBytes->Length ));
   ascii->GetChars( asciiBytes, 0, asciiBytes->Length, asciiChars, 0 );
   String^ asciiString = gcnew String( asciiChars );
   
   // Display the strings created before and after the conversion.
   Console::WriteLine( "Original String*: {0}", unicodeString );
   Console::WriteLine( "Ascii converted String*: {0}", asciiString );
}
// The example displays the following output:
//    Original string: This string contains the unicode character Pi (Π)
//    Ascii converted string: This string contains the unicode character Pi (?)
using System;
using System.Text;

class Example
{
   static void Main()
   {
      string unicodeString = "This string contains the unicode character Pi (\u03a0)";

      // Create two different encodings.
      Encoding ascii = Encoding.ASCII;
      Encoding unicode = Encoding.Unicode;

      // Convert the string into a byte array.
      byte[] unicodeBytes = unicode.GetBytes(unicodeString);

      // Perform the conversion from one encoding to the other.
      byte[] asciiBytes = Encoding.Convert(unicode, ascii, unicodeBytes);
         
      // Convert the new byte[] into a char[] and then into a string.
      char[] asciiChars = new char[ascii.GetCharCount(asciiBytes, 0, asciiBytes.Length)];
      ascii.GetChars(asciiBytes, 0, asciiBytes.Length, asciiChars, 0);
      string asciiString = new string(asciiChars);

      // Display the strings created before and after the conversion.
      Console.WriteLine("Original string: {0}", unicodeString);
      Console.WriteLine("Ascii converted string: {0}", asciiString);
   }
}
// The example displays the following output:
//    Original string: This string contains the unicode character Pi (Π)
//    Ascii converted string: This string contains the unicode character Pi (?)
Imports System.Text

Class Example
   Shared Sub Main()
      Dim unicodeString As String = "This string contains the unicode character Pi (" & ChrW(&H03A0) & ")"

      ' Create two different encodings.
      Dim ascii As Encoding = Encoding.ASCII
      Dim unicode As Encoding = Encoding.Unicode

      ' Convert the string into a byte array.
      Dim unicodeBytes As Byte() = unicode.GetBytes(unicodeString)

      ' Perform the conversion from one encoding to the other.
      Dim asciiBytes As Byte() = Encoding.Convert(unicode, ascii, unicodeBytes)

      ' Convert the new byte array into a char array and then into a string.
      Dim asciiChars(ascii.GetCharCount(asciiBytes, 0, asciiBytes.Length)-1) As Char
      ascii.GetChars(asciiBytes, 0, asciiBytes.Length, asciiChars, 0)
      Dim asciiString As New String(asciiChars)

      ' Display the strings created before and after the conversion.
      Console.WriteLine("Original string: {0}", unicodeString)
      Console.WriteLine("Ascii converted string: {0}", asciiString)
   End Sub
End Class
' The example displays the following output:
'    Original string: This string contains the unicode character Pi (Π)
'    Ascii converted string: This string contains the unicode character Pi (?)

El ejemplo siguiente codifica una cadena en una matriz de bytes y, a continuación, descodifica un intervalo de bytes en una matriz de caracteres.The following example encodes a string into an array of bytes, and then decodes a range of the bytes into an array of characters.

using namespace System;
using namespace System::Text;
void PrintCountsAndChars( array<Byte>^bytes, int index, int count, Encoding^ enc );
int main()
{
   
   // Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
   Encoding^ u32LE = Encoding::GetEncoding( "utf-32" );
   Encoding^ u32BE = Encoding::GetEncoding( "utf-32BE" );
   
   // Use a string containing the following characters:
   //    Latin Small Letter Z (U+007A)
   //    Latin Small Letter A (U+0061)
   //    Combining Breve (U+0306)
   //    Latin Small Letter AE With Acute (U+01FD)
   //    Greek Small Letter Beta (U+03B2)
   String^ myStr = "za\u0306\u01FD\u03B2";
   
   // Encode the string using the big-endian byte order.
   array<Byte>^barrBE = gcnew array<Byte>(u32BE->GetByteCount( myStr ));
   u32BE->GetBytes( myStr, 0, myStr->Length, barrBE, 0 );
   
   // Encode the string using the little-endian byte order.
   array<Byte>^barrLE = gcnew array<Byte>(u32LE->GetByteCount( myStr ));
   u32LE->GetBytes( myStr, 0, myStr->Length, barrLE, 0 );
   
   // Get the char counts, decode eight bytes starting at index 0,
   // and print out the counts and the resulting bytes.
   Console::Write( "BE array with BE encoding : " );
   PrintCountsAndChars( barrBE, 0, 8, u32BE );
   Console::Write( "LE array with LE encoding : " );
   PrintCountsAndChars( barrLE, 0, 8, u32LE );
}

void PrintCountsAndChars( array<Byte>^bytes, int index, int count, Encoding^ enc )
{
   
   // Display the name of the encoding used.
   Console::Write( "{0,-25} :", enc );
   
   // Display the exact character count.
   int iCC = enc->GetCharCount( bytes, index, count );
   Console::Write( " {0,-3}", iCC );
   
   // Display the maximum character count.
   int iMCC = enc->GetMaxCharCount( count );
   Console::Write( " {0,-3} :", iMCC );
   
   // Decode the bytes and display the characters.
   array<Char>^chars = enc->GetChars( bytes, index, count );
   
   // The following is an alternative way to decode the bytes:
   // Char[] chars = new Char[iCC];
   // enc->GetChars( bytes, index, count, chars, 0 );
   Console::WriteLine( chars );
}

/* 
This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.

BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za

*/
using System;
using System.Text;

public class SamplesEncoding  {

   public static void Main()  {

      // Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
      Encoding u32LE = Encoding.GetEncoding( "utf-32" );
      Encoding u32BE = Encoding.GetEncoding( "utf-32BE" );

      // Use a string containing the following characters:
      //    Latin Small Letter Z (U+007A)
      //    Latin Small Letter A (U+0061)
      //    Combining Breve (U+0306)
      //    Latin Small Letter AE With Acute (U+01FD)
      //    Greek Small Letter Beta (U+03B2)
      String myStr = "za\u0306\u01FD\u03B2";

      // Encode the string using the big-endian byte order.
      byte[] barrBE = new byte[u32BE.GetByteCount( myStr )];
      u32BE.GetBytes( myStr, 0, myStr.Length, barrBE, 0 );

      // Encode the string using the little-endian byte order.
      byte[] barrLE = new byte[u32LE.GetByteCount( myStr )];
      u32LE.GetBytes( myStr, 0, myStr.Length, barrLE, 0 );

      // Get the char counts, decode eight bytes starting at index 0,
      // and print out the counts and the resulting bytes.
      Console.Write( "BE array with BE encoding : " );
      PrintCountsAndChars( barrBE, 0, 8, u32BE );
      Console.Write( "LE array with LE encoding : " );
      PrintCountsAndChars( barrLE, 0, 8, u32LE );

   }


   public static void PrintCountsAndChars( byte[] bytes, int index, int count, Encoding enc )  {

      // Display the name of the encoding used.
      Console.Write( "{0,-25} :", enc.ToString() );

      // Display the exact character count.
      int iCC  = enc.GetCharCount( bytes, index, count );
      Console.Write( " {0,-3}", iCC );

      // Display the maximum character count.
      int iMCC = enc.GetMaxCharCount( count );
      Console.Write( " {0,-3} :", iMCC );

      // Decode the bytes and display the characters.
      char[] chars = enc.GetChars( bytes, index, count );

      // The following is an alternative way to decode the bytes:
      // char[] chars = new char[iCC];
      // enc.GetChars( bytes, index, count, chars, 0 );

      Console.WriteLine( chars );

   }

}


/* 
This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.

BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za

*/

Imports System
Imports System.Text
Imports Microsoft.VisualBasic

Public Class SamplesEncoding   

   Public Shared Sub Main()

      ' Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
      Dim u32LE As Encoding = Encoding.GetEncoding("utf-32")
      Dim u32BE As Encoding = Encoding.GetEncoding("utf-32BE")

      ' Use a string containing the following characters:
      '    Latin Small Letter Z (U+007A)
      '    Latin Small Letter A (U+0061)
      '    Combining Breve (U+0306)
      '    Latin Small Letter AE With Acute (U+01FD)
      '    Greek Small Letter Beta (U+03B2)
      Dim myStr As String = "za" & ChrW(&H0306) & ChrW(&H01FD) & ChrW(&H03B2)

      ' Encode the string using the big-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates barrBE with the exact number of elements required.
      Dim barrBE(u32BE.GetByteCount(myStr) - 1) As Byte
      u32BE.GetBytes(myStr, 0, myStr.Length, barrBE, 0)

      ' Encode the string using the little-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates barrLE with the exact number of elements required.
      Dim barrLE(u32LE.GetByteCount(myStr) - 1) As Byte
      u32LE.GetBytes(myStr, 0, myStr.Length, barrLE, 0)

      ' Get the char counts, decode eight bytes starting at index 0,
      ' and print out the counts and the resulting bytes.
      Console.Write("BE array with BE encoding : ")
      PrintCountsAndChars(barrBE, 0, 8, u32BE)
      Console.Write("LE array with LE encoding : ")
      PrintCountsAndChars(barrLE, 0, 8, u32LE)

   End Sub 'Main


   Public Shared Sub PrintCountsAndChars(bytes() As Byte, index As Integer, count As Integer, enc As Encoding)

      ' Display the name of the encoding used.
      Console.Write("{0,-25} :", enc.ToString())

      ' Display the exact character count.
      Dim iCC As Integer = enc.GetCharCount(bytes, index, count)
      Console.Write(" {0,-3}", iCC)

      ' Display the maximum character count.
      Dim iMCC As Integer = enc.GetMaxCharCount(count)
      Console.Write(" {0,-3} :", iMCC)

      ' Decode the bytes.
      Dim chars As Char() = enc.GetChars(bytes, index, count)

      ' The following is an alternative way to decode the bytes:
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates the array with the exact number of elements required.
      ' Dim chars(iCC - 1) As Char
      ' enc.GetChars( bytes, index, count, chars, 0 )

      ' Display the characters.
      Console.WriteLine(chars)

   End Sub 'PrintCountsAndChars 

End Class 'SamplesEncoding


'This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.
'
'BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
'LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za

Comentarios

Para calcular el tamaño exacto de matriz requerido GetChars para almacenar los caracteres resultantes, debe usar el GetCharCount método.To calculate the exact array size required by GetChars to store the resulting characters, you should use the GetCharCount method. Para calcular el tamaño máximo de la matriz, use el GetMaxCharCount método.To calculate the maximum array size, use the GetMaxCharCount method. El GetCharCount método generalmente permite asignar menos memoria, mientras que el GetMaxCharCount método generalmente se ejecuta con mayor rapidez.The GetCharCount method generally allows allocation of less memory, while the GetMaxCharCount method generally executes faster.

[], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A?displayProperty=nameWithType > obtiene caracteres de una secuencia de bytes de entrada.[], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A?displayProperty=nameWithType> gets characters from an input byte sequence. [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A?displayProperty=nameWithType > es diferente de Decoder.GetChars porque Encoding espera conversiones discretas, mientras que Decoder está diseñada para varios pasos en un único flujo de entrada.[], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A?displayProperty=nameWithType> is different than Decoder.GetChars because Encoding expects discrete conversions, while Decoder is designed for multiple passes on a single input stream.

Si los datos que se va a convertir están disponibles sólo en bloques secuenciales (como los datos leídos de una secuencia) o si la cantidad de datos es tan grande que debe dividirse en bloques más pequeños, se debe usar el Decoder o Encoder proporcionada por el GetDecoder método o la GetEncoder método, respectivamente, de una clase derivada.If the data to be converted is available only in sequential blocks (such as data read from a stream) or if the amount of data is so large that it needs to be divided into smaller blocks, you should use the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively, of a derived class.

Tenga en cuenta este método está pensado para operar en caracteres Unicode, no en los datos binarios arbitrarios, como matrices de bytes.Note This method is intended to operate on Unicode characters, not on arbitrary binary data, such as byte arrays. Si tiene que codificar datos binarios arbitrarios en texto, debe usar un protocolo como uuencode, que se implementa mediante métodos como Convert.ToBase64CharArray.If you need to encode arbitrary binary data into text, you should use a protocol such as uuencode, which is implemented by methods such as Convert.ToBase64CharArray.

El GetCharCount método determina el número de caracteres resultante de descodificar una secuencia de bytes y el GetChars método realiza la descodificación real.The GetCharCount method determines how many characters result in decoding a sequence of bytes, and the GetChars method performs the actual decoding. El Encoding.GetChars método espera conversiones discretas, en contraposición al Decoder.GetChars método, que administra varios pasos en un único flujo de entrada.The Encoding.GetChars method expects discrete conversions, in contrast to the Decoder.GetChars method, which handles multiple passes on a single input stream.

Varias versiones de GetCharCount y GetChars son compatibles.Several versions of GetCharCount and GetChars are supported. Éstas son algunas consideraciones de programación para su uso de estos métodos:The following are some programming considerations for use of these methods:

  • La aplicación deba descodificar varios bytes de entrada de una página de códigos y procesar los bytes mediante varias llamadas.Your app might need to decode multiple input bytes from a code page and process the bytes using multiple calls. En este caso, probablemente necesite mantener el estado entre llamadas, porque se pueden interrumpir las secuencias de bytes cuando se procesen en lotes.In this case, you probably need to maintain state between calls, because byte sequences can be interrupted when processed in batches. (Por ejemplo, puede finalizar la parte de una secuencia de ISO-2022 MAYÚS uno [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A > llamar y continuar desde el principio del siguiente [], Int32, Int32, Char<xref : System.Text.Encoding.GetChars%2A > llamar.(For example, part of an ISO-2022 shift sequence may end one [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A> call and continue at the beginning of the next [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A> call. [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A?displayProperty=nameWithType > llamará a la reserva para esas secuencias incompletas, pero Decoder recordará esas secuencias para la siguiente llamada.)[], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%2A?displayProperty=nameWithType> will call the fallback for those incomplete sequences, but Decoder will remember those sequences for the next call.)

  • Si la aplicación administra los resultados de la cadena, la GetString método es recomendable.If your app handles string outputs, the GetString method is recommended. Dado que este método debe comprobar la longitud de cadena y asignar un búfer, es algo más lento, pero resultante String tipo es preferible.Since this method must check string length and allocate a buffer, it is slightly slower, but the resulting String type is to be preferred.

  • La versión de bytes de GetChars(Byte*, Int32, Char*, Int32) permite algunas técnicas rápidas, especialmente con varias llamadas a los búferes grandes.The byte version of GetChars(Byte*, Int32, Char*, Int32) allows some fast techniques, particularly with multiple calls to large buffers. Tenga en cuenta, sin embargo, esta versión del método a veces es segura, puesto que los punteros son necesarios.Bear in mind, however, that this method version is sometimes unsafe, since pointers are required.

  • Si la aplicación debe convertir una gran cantidad de datos, debe volver a usar el búfer de salida.If your app must convert a large amount of data, it should reuse the output buffer. En este caso, el [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29 > versión que admite caracteres de salida búferes es la mejor opción.In this case, the [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29> version that supports output character buffers is the best choice.

  • Considere el uso de la Decoder.Convert método en lugar de GetCharCount.Consider using the Decoder.Convert method instead of GetCharCount. El método de conversión convierte tantos datos como sea posible y produce una excepción si el búfer de salida es demasiado pequeño.The conversion method converts as much data as possible and throws an exception if the output buffer is too small. Para la descodificación continua de un flujo, este método suele ser la mejor opción.For continuous decoding of a stream, this method is often the best choice.

Consultar también

GetChars(Byte*, Int32, Char*, Int32) GetChars(Byte*, Int32, Char*, Int32) GetChars(Byte*, Int32, Char*, Int32)

Importante

Esta API no es conforme a CLS.

Cuando se reemplaza en una clase derivada, descodifica una secuencia de bytes a partir del puntero de bytes especificado en un juego de caracteres que se almacenan a partir del puntero de caracteres especificado. When overridden in a derived class, decodes a sequence of bytes starting at the specified byte pointer into a set of characters that are stored starting at the specified character pointer.

public:
 virtual int GetChars(System::Byte* bytes, int byteCount, char* chars, int charCount);
[System.CLSCompliant(false)]
[System.Runtime.InteropServices.ComVisible(false)]
[System.Security.SecurityCritical]
public virtual int GetChars (byte* bytes, int byteCount, char* chars, int charCount);
abstract member GetChars : nativeptr<byte> * int * nativeptr<char> * int -> int
override this.GetChars : nativeptr<byte> * int * nativeptr<char> * int -> int

Parámetros

bytes
Byte*

Puntero al primer byte que se va a descodificar. A pointer to the first byte to decode.

byteCount
Int32 Int32 Int32 Int32

Número de bytes que se van a descodificar. The number of bytes to decode.

chars
Char*

Puntero a la ubicación en la que se iniciará la escritura del juego de caracteres resultante. A pointer to the location at which to start writing the resulting set of characters.

charCount
Int32 Int32 Int32 Int32

Número máximo de caracteres que se van a escribir. The maximum number of characters to write.

Devoluciones

Número real de caracteres escritos en la ubicación indicada por el parámetro chars. The actual number of characters written at the location indicated by the chars parameter.

Excepciones

El valor de bytes es null. bytes is null. O bien -or- El valor de chars es null. chars is null.

byteCount o charCount es menor que cero. byteCount or charCount is less than zero.

El valor de charCount es menor que el número de caracteres resultante. charCount is less than the resulting number of characters.

Se ha producido una acción de reserva (vea Codificación de caracteres de .NET para obtener una explicación completa) A fallback occurred (see Character Encoding in .NET for complete explanation) - y - -and- El valor de DecoderFallback está establecido en DecoderExceptionFallback. DecoderFallback is set to DecoderExceptionFallback.

Comentarios

La matriz exacta para calcular el tamaño que GetChars requiere para almacenar los caracteres resultantes, debe usar el GetCharCount método.To calculate the exact array size that GetChars requires to store the resulting characters, you should use the GetCharCount method. Para calcular el tamaño máximo de la matriz, use el GetMaxCharCount método.To calculate the maximum array size, use the GetMaxCharCount method. El GetCharCount método generalmente permite asignar menos memoria, mientras que el GetMaxCharCount método generalmente se ejecuta con mayor rapidez.The GetCharCount method generally allows allocation of less memory, while the GetMaxCharCount method generally executes faster.

Encoding.GetChars Obtiene los caracteres de una secuencia de bytes de entrada.Encoding.GetChars gets characters from an input byte sequence. Encoding.GetChars es diferente de Decoder.GetChars porque Encoding espera conversiones discretas, mientras que Decoder está diseñado para varios pasos en un único flujo de entrada.Encoding.GetChars is different than Decoder.GetChars because Encoding expects discrete conversions, while Decoder is designed for multiple passes on a single input stream.

Si los datos que se va a convertir están disponibles sólo en bloques secuenciales (como los datos leídos de una secuencia) o si la cantidad de datos es tan grande que debe dividirse en bloques más pequeños, se debe usar el Decoder o Encoder objeto proporcionado por el GetDecoder o GetEncoder método, respectivamente, de una clase derivada.If the data to be converted is available only in sequential blocks (such as data read from a stream) or if the amount of data is so large that it needs to be divided into smaller blocks, you should use the Decoder or the Encoder object provided by the GetDecoder or the GetEncoder method, respectively, of a derived class.

Tenga en cuenta este método está pensado para operar en caracteres Unicode, no en los datos binarios arbitrarios, como matrices de bytes.Note This method is intended to operate on Unicode characters, not on arbitrary binary data, such as byte arrays. Si tiene que codificar datos binarios arbitrarios en texto, debe usar un protocolo como uuencode, que se implementa mediante métodos como Convert.ToBase64CharArray.If you need to encode arbitrary binary data into text, you should use a protocol such as uuencode, which is implemented by methods such as Convert.ToBase64CharArray.

El GetCharCount método determina el número de caracteres resultante de descodificar una secuencia de bytes y el GetChars método realiza la descodificación real.The GetCharCount method determines how many characters result in decoding a sequence of bytes, and the GetChars method performs the actual decoding. El Encoding.GetChars método espera conversiones discretas, en contraposición al Decoder.GetChars método, que administra varios pasos en un único flujo de entrada.The Encoding.GetChars method expects discrete conversions, in contrast to the Decoder.GetChars method, which handles multiple passes on a single input stream.

Varias versiones de GetCharCount y GetChars son compatibles.Several versions of GetCharCount and GetChars are supported. Éstas son algunas consideraciones de programación para su uso de estos métodos:The following are some programming considerations for use of these methods:

  • La aplicación deba descodificar varios bytes de entrada de una página de códigos y procesar los bytes mediante varias llamadas.Your app might need to decode multiple input bytes from a code page and process the bytes using multiple calls. En este caso, probablemente necesite mantener el estado entre llamadas, porque se pueden interrumpir las secuencias de bytes cuando se procesen en lotes.In this case, you probably need to maintain state between calls, because byte sequences can be interrupted when processed in batches. (Por ejemplo, puede finalizar la parte de una secuencia de ISO-2022 MAYÚS uno GetChars llamar y continuar desde el principio del siguiente GetChars llamar.(For example, part of an ISO-2022 shift sequence may end one GetChars call and continue at the beginning of the next GetChars call. Encoding.GetChars llamará a la reserva para esas secuencias incompletas, pero Decoder recordará esas secuencias para la siguiente llamada.)Encoding.GetChars will call the fallback for those incomplete sequences, but Decoder will remember those sequences for the next call.)

  • Si la aplicación administra los resultados de la cadena, la GetString método es recomendable.If your app handles string outputs, the GetString method is recommended. Dado que este método debe comprobar la longitud de cadena y asignar un búfer, es algo más lento, pero resultante String tipo es preferible.Since this method must check string length and allocate a buffer, it is slightly slower, but the resulting String type is to be preferred.

  • La versión de bytes de GetChars(Byte*, Int32, Char*, Int32) permite algunas técnicas rápidas, especialmente con varias llamadas a los búferes grandes.The byte version of GetChars(Byte*, Int32, Char*, Int32) allows some fast techniques, particularly with multiple calls to large buffers. Tenga en cuenta, sin embargo, esta versión del método a veces es segura, puesto que los punteros son necesarios.Bear in mind, however, that this method version is sometimes unsafe, since pointers are required.

  • Si la aplicación debe convertir una gran cantidad de datos, debe volver a usar el búfer de salida.If your app must convert a large amount of data, it should reuse the output buffer. En este caso, el [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29 > versión que admite caracteres de salida búferes es la mejor opción.In this case, the [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29> version that supports output character buffers is the best choice.

  • Considere el uso de la Decoder.Convert método en lugar de GetCharCount.Consider using the Decoder.Convert method instead of GetCharCount. El método de conversión convierte tantos datos como sea posible y produce una excepción si el búfer de salida es demasiado pequeño.The conversion method converts as much data as possible and throws an exception if the output buffer is too small. Para la descodificación continua de un flujo, este método suele ser la mejor opción.For continuous decoding of a stream, this method is often the best choice.

Seguridad

SecurityCriticalAttribute
requiere plena confianza para el llamador inmediato. Requires full trust for the immediate caller. Este miembro no se puede usar código de confianza parcial o transparente. This member cannot be used by partially trusted or transparent code.

Consultar también

GetChars(ReadOnlySpan<Byte>, Span<Char>) GetChars(ReadOnlySpan<Byte>, Span<Char>) GetChars(ReadOnlySpan<Byte>, Span<Char>) GetChars(ReadOnlySpan<Byte>, Span<Char>)

public:
 virtual int GetChars(ReadOnlySpan<System::Byte> bytes, Span<char> chars);
public virtual int GetChars (ReadOnlySpan<byte> bytes, Span<char> chars);
abstract member GetChars : ReadOnlySpan<byte> * Span<char> -> int
override this.GetChars : ReadOnlySpan<byte> * Span<char> -> int
Public Overridable Function GetChars (bytes As ReadOnlySpan(Of Byte), chars As Span(Of Char)) As Integer

Parámetros

chars
Span<Char>

Devoluciones

GetChars(Byte[]) GetChars(Byte[]) GetChars(Byte[]) GetChars(Byte[])

Cuando se reemplaza en una clase derivada, descodifica todos los bytes de la matriz de bytes especificada en un juego de caracteres. When overridden in a derived class, decodes all the bytes in the specified byte array into a set of characters.

public:
 virtual cli::array <char> ^ GetChars(cli::array <System::Byte> ^ bytes);
public virtual char[] GetChars (byte[] bytes);
abstract member GetChars : byte[] -> char[]
override this.GetChars : byte[] -> char[]
Public Overridable Function GetChars (bytes As Byte()) As Char()

Parámetros

bytes
Byte[]

Matriz de bytes que contiene la secuencia de bytes que se va a descodificar. The byte array containing the sequence of bytes to decode.

Devoluciones

Char[]

Matriz de caracteres que contiene los resultados obtenidos al descodificar la secuencia de bytes especificada. A character array containing the results of decoding the specified sequence of bytes.

Excepciones

Se ha producido una acción de reserva (vea Codificación de caracteres de .NET para obtener una explicación completa) A fallback occurred (see Character Encoding in .NET for complete explanation) - y - -and- El valor de DecoderFallback está establecido en DecoderExceptionFallback. DecoderFallback is set to DecoderExceptionFallback.

Ejemplos

El ejemplo siguiente codifica una cadena en una matriz de bytes y, a continuación, descodifica los bytes en una matriz de caracteres.The following example encodes a string into an array of bytes, and then decodes the bytes into an array of characters.

using namespace System;
using namespace System::Text;
void PrintCountsAndChars( array<Byte>^bytes, Encoding^ enc );
int main()
{
   
   // Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
   Encoding^ u32LE = Encoding::GetEncoding( "utf-32" );
   Encoding^ u32BE = Encoding::GetEncoding( "utf-32BE" );
   
   // Use a string containing the following characters:
   //    Latin Small Letter Z (U+007A)
   //    Latin Small Letter A (U+0061)
   //    Combining Breve (U+0306)
   //    Latin Small Letter AE With Acute (U+01FD)
   //    Greek Small Letter Beta (U+03B2)
   String^ myStr = "za\u0306\u01FD\u03B2";
   
   // Encode the string using the big-endian byte order.
   array<Byte>^barrBE = gcnew array<Byte>(u32BE->GetByteCount( myStr ));
   u32BE->GetBytes( myStr, 0, myStr->Length, barrBE, 0 );
   
   // Encode the string using the little-endian byte order.
   array<Byte>^barrLE = gcnew array<Byte>(u32LE->GetByteCount( myStr ));
   u32LE->GetBytes( myStr, 0, myStr->Length, barrLE, 0 );
   
   // Get the char counts, and decode the byte arrays.
   Console::Write( "BE array with BE encoding : " );
   PrintCountsAndChars( barrBE, u32BE );
   Console::Write( "LE array with LE encoding : " );
   PrintCountsAndChars( barrLE, u32LE );
}

void PrintCountsAndChars( array<Byte>^bytes, Encoding^ enc )
{
   
   // Display the name of the encoding used.
   Console::Write( "{0,-25} :", enc );
   
   // Display the exact character count.
   int iCC = enc->GetCharCount( bytes );
   Console::Write( " {0,-3}", iCC );
   
   // Display the maximum character count.
   int iMCC = enc->GetMaxCharCount( bytes->Length );
   Console::Write( " {0,-3} :", iMCC );
   
   // Decode the bytes and display the characters.
   array<Char>^chars = enc->GetChars( bytes );
   Console::WriteLine( chars );
}

/* 
This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.

BE array with BE encoding : System.Text.UTF32Encoding : 5   12  :za??�
LE array with LE encoding : System.Text.UTF32Encoding : 5   12  :za??�

*/
using System;
using System.Text;

public class SamplesEncoding  {

   public static void Main()  {

      // Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
      Encoding u32LE = Encoding.GetEncoding( "utf-32" );
      Encoding u32BE = Encoding.GetEncoding( "utf-32BE" );

      // Use a string containing the following characters:
      //    Latin Small Letter Z (U+007A)
      //    Latin Small Letter A (U+0061)
      //    Combining Breve (U+0306)
      //    Latin Small Letter AE With Acute (U+01FD)
      //    Greek Small Letter Beta (U+03B2)
      String myStr = "za\u0306\u01FD\u03B2";

      // Encode the string using the big-endian byte order.
      byte[] barrBE = new byte[u32BE.GetByteCount( myStr )];
      u32BE.GetBytes( myStr, 0, myStr.Length, barrBE, 0 );

      // Encode the string using the little-endian byte order.
      byte[] barrLE = new byte[u32LE.GetByteCount( myStr )];
      u32LE.GetBytes( myStr, 0, myStr.Length, barrLE, 0 );

      // Get the char counts, and decode the byte arrays.
      Console.Write( "BE array with BE encoding : " );
      PrintCountsAndChars( barrBE, u32BE );
      Console.Write( "LE array with LE encoding : " );
      PrintCountsAndChars( barrLE, u32LE );

   }


   public static void PrintCountsAndChars( byte[] bytes, Encoding enc )  {

      // Display the name of the encoding used.
      Console.Write( "{0,-25} :", enc.ToString() );

      // Display the exact character count.
      int iCC  = enc.GetCharCount( bytes );
      Console.Write( " {0,-3}", iCC );

      // Display the maximum character count.
      int iMCC = enc.GetMaxCharCount( bytes.Length );
      Console.Write( " {0,-3} :", iMCC );

      // Decode the bytes and display the characters.
      char[] chars = enc.GetChars( bytes );
      Console.WriteLine( chars );

   }

}


/* 
This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.

BE array with BE encoding : System.Text.UTF32Encoding : 5   12  :za??�
LE array with LE encoding : System.Text.UTF32Encoding : 5   12  :za??�

*/

Imports System
Imports System.Text
Imports Microsoft.VisualBasic

Public Class SamplesEncoding   

   Public Shared Sub Main()

      ' Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
      Dim u32LE As Encoding = Encoding.GetEncoding("utf-32")
      Dim u32BE As Encoding = Encoding.GetEncoding("utf-32BE")

      ' Use a string containing the following characters:
      '    Latin Small Letter Z (U+007A)
      '    Latin Small Letter A (U+0061)
      '    Combining Breve (U+0306)
      '    Latin Small Letter AE With Acute (U+01FD)
      '    Greek Small Letter Beta (U+03B2)
      Dim myStr As String = "za" & ChrW(&H0306) & ChrW(&H01FD) & ChrW(&H03B2) 

      ' Encode the string using the big-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates the array with the exact number of elements required.
      Dim barrBE(u32BE.GetByteCount(myStr) - 1) As Byte
      u32BE.GetBytes(myStr, 0, myStr.Length, barrBE, 0)

      ' Encode the string using the little-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates the array with the exact number of elements required.
      Dim barrLE(u32LE.GetByteCount(myStr) - 1) As Byte
      u32LE.GetBytes(myStr, 0, myStr.Length, barrLE, 0)

      ' Get the char counts, and decode the byte arrays.
      Console.Write("BE array with BE encoding : ")
      PrintCountsAndChars(barrBE, u32BE)
      Console.Write("LE array with LE encoding : ")
      PrintCountsAndChars(barrLE, u32LE)

   End Sub 'Main


   Public Shared Sub PrintCountsAndChars(bytes() As Byte, enc As Encoding)

      ' Display the name of the encoding used.
      Console.Write("{0,-25} :", enc.ToString())

      ' Display the exact character count.
      Dim iCC As Integer = enc.GetCharCount(bytes)
      Console.Write(" {0,-3}", iCC)

      ' Display the maximum character count.
      Dim iMCC As Integer = enc.GetMaxCharCount(bytes.Length)
      Console.Write(" {0,-3} :", iMCC)

      ' Decode the bytes and display the characters.
      Dim chars As Char() = enc.GetChars(bytes)
      Console.WriteLine(chars)

   End Sub 'PrintCountsAndChars 

End Class 'SamplesEncoding


'This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.
'
'BE array with BE encoding : System.Text.UTF32Encoding : 5   12  :za??�
'LE array with LE encoding : System.Text.UTF32Encoding : 5   12  :za??�

Comentarios

Encoding.GetChars Obtiene los caracteres de una secuencia de bytes de entrada.Encoding.GetChars gets characters from an input byte sequence. Encoding.GetChars es diferente de Decoder.GetChars porque Encoding espera conversiones discretas, mientras que Decoder está diseñado para varios pasos en un único flujo de entrada.Encoding.GetChars is different than Decoder.GetChars because Encoding expects discrete conversions, while Decoder is designed for multiple passes on a single input stream.

Si los datos que se va a convertir están disponibles sólo en bloques secuenciales (como los datos leídos de una secuencia) o si la cantidad de datos es tan grande que debe dividirse en bloques más pequeños, se debe usar el Decoder o Encoder proporcionada por el GetDecoder método o la GetEncoder método, respectivamente, de una clase derivada.If the data to be converted is available only in sequential blocks (such as data read from a stream) or if the amount of data is so large that it needs to be divided into smaller blocks, you should use the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively, of a derived class.

Tenga en cuenta este método está pensado para operar en caracteres Unicode, no en los datos binarios arbitrarios, como matrices de bytes.Note This method is intended to operate on Unicode characters, not on arbitrary binary data, such as byte arrays. Si tiene que codificar datos binarios arbitrarios en texto, debe usar un protocolo como uuencode, que se implementa mediante métodos como Convert.ToBase64CharArray.If you need to encode arbitrary binary data into text, you should use a protocol such as uuencode, which is implemented by methods such as Convert.ToBase64CharArray.

El GetCharCount método determina el número de caracteres resultante de descodificar una secuencia de bytes y el GetChars método realiza la descodificación real.The GetCharCount method determines how many characters result in decoding a sequence of bytes, and the GetChars method performs the actual decoding. El Encoding.GetChars método espera conversiones discretas, en contraposición al Decoder.GetChars método, que administra varios pasos en un único flujo de entrada.The Encoding.GetChars method expects discrete conversions, in contrast to the Decoder.GetChars method, which handles multiple passes on a single input stream.

Varias versiones de GetCharCount y GetChars son compatibles.Several versions of GetCharCount and GetChars are supported. Éstas son algunas consideraciones de programación para su uso de estos métodos:The following are some programming considerations for use of these methods:

  • La aplicación deba descodificar varios bytes de entrada de una página de códigos y procesar los bytes mediante varias llamadas.Your app might need to decode multiple input bytes from a code page and process the bytes using multiple calls. En este caso, probablemente necesite mantener el estado entre llamadas, porque se pueden interrumpir las secuencias de bytes cuando se procesen en lotes.In this case, you probably need to maintain state between calls, because byte sequences can be interrupted when processed in batches. (Por ejemplo, puede finalizar la parte de una secuencia de ISO-2022 MAYÚS uno GetChars llamar y continuar desde el principio del siguiente GetChars llamar.(For example, part of an ISO-2022 shift sequence may end one GetChars call and continue at the beginning of the next GetChars call. Encoding.GetChars llamará a la reserva para esas secuencias incompletas, pero Decoder recordará esas secuencias para la siguiente llamada.)Encoding.GetChars will call the fallback for those incomplete sequences, but Decoder will remember those sequences for the next call.)

  • Si la aplicación administra los resultados de la cadena, se recomienda utilizar la GetString método.If your app handles string outputs, it is recommended to use the GetString method. Dado que este método debe comprobar la longitud de cadena y asignar un búfer, es algo más lento, pero resultante String tipo es preferible.Since this method must check string length and allocate a buffer, it is slightly slower, but the resulting String type is to be preferred.

  • La versión de bytes de GetChars(Byte*, Int32, Char*, Int32) permite algunas técnicas rápidas, especialmente con varias llamadas a los búferes grandes.The byte version of GetChars(Byte*, Int32, Char*, Int32) allows some fast techniques, particularly with multiple calls to large buffers. Tenga en cuenta, sin embargo, esta versión del método a veces es segura, puesto que los punteros son necesarios.Bear in mind, however, that this method version is sometimes unsafe, since pointers are required.

  • Si la aplicación debe convertir una gran cantidad de datos, debe volver a usar el búfer de salida.If your app must convert a large amount of data, it should reuse the output buffer. En este caso, el [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29 > versión que admite caracteres de salida búferes es la mejor opción.In this case, the [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29> version that supports output character buffers is the best choice.

  • Considere el uso de la Decoder.Convert método en lugar de GetCharCount.Consider using the Decoder.Convert method instead of GetCharCount. El método de conversión convierte tantos datos como sea posible y produce una excepción si el búfer de salida es demasiado pequeño.The conversion method converts as much data as possible and throws an exception if the output buffer is too small. Para la descodificación continua de un flujo, este método suele ser la mejor opción.For continuous decoding of a stream, this method is often the best choice.

Consultar también

GetChars(Byte[], Int32, Int32) GetChars(Byte[], Int32, Int32) GetChars(Byte[], Int32, Int32) GetChars(Byte[], Int32, Int32)

Cuando se reemplaza en una clase derivada, descodifica una secuencia de bytes de la matriz de bytes especificada en un juego de caracteres. When overridden in a derived class, decodes a sequence of bytes from the specified byte array into a set of characters.

public:
 virtual cli::array <char> ^ GetChars(cli::array <System::Byte> ^ bytes, int index, int count);
public virtual char[] GetChars (byte[] bytes, int index, int count);
abstract member GetChars : byte[] * int * int -> char[]
override this.GetChars : byte[] * int * int -> char[]
Public Overridable Function GetChars (bytes As Byte(), index As Integer, count As Integer) As Char()

Parámetros

bytes
Byte[]

Matriz de bytes que contiene la secuencia de bytes que se va a descodificar. The byte array containing the sequence of bytes to decode.

index
Int32 Int32 Int32 Int32

Índice del primer byte que se va a descodificar. The index of the first byte to decode.

count
Int32 Int32 Int32 Int32

Número de bytes que se van a descodificar. The number of bytes to decode.

Devoluciones

Char[]

Matriz de caracteres que contiene los resultados obtenidos al descodificar la secuencia de bytes especificada. A character array containing the results of decoding the specified sequence of bytes.

Excepciones

index o count es menor que cero. index or count is less than zero. O bien -or- index y count no denotan un intervalo válido en bytes. index and count do not denote a valid range in bytes.

Se ha producido una acción de reserva (vea Codificación de caracteres de .NET para obtener una explicación completa) A fallback occurred (see Character Encoding in .NET for complete explanation) - y - -and- El valor de DecoderFallback está establecido en DecoderExceptionFallback. DecoderFallback is set to DecoderExceptionFallback.

Ejemplos

El ejemplo siguiente codifica una cadena en una matriz de bytes y, a continuación, descodifica un intervalo de bytes en una matriz de caracteres.The following example encodes a string into an array of bytes, and then decodes a range of the bytes into an array of characters.

using namespace System;
using namespace System::Text;
void PrintCountsAndChars( array<Byte>^bytes, int index, int count, Encoding^ enc );
int main()
{
   
   // Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
   Encoding^ u32LE = Encoding::GetEncoding( "utf-32" );
   Encoding^ u32BE = Encoding::GetEncoding( "utf-32BE" );
   
   // Use a string containing the following characters:
   //    Latin Small Letter Z (U+007A)
   //    Latin Small Letter A (U+0061)
   //    Combining Breve (U+0306)
   //    Latin Small Letter AE With Acute (U+01FD)
   //    Greek Small Letter Beta (U+03B2)
   String^ myStr = "za\u0306\u01FD\u03B2";
   
   // Encode the string using the big-endian byte order.
   array<Byte>^barrBE = gcnew array<Byte>(u32BE->GetByteCount( myStr ));
   u32BE->GetBytes( myStr, 0, myStr->Length, barrBE, 0 );
   
   // Encode the string using the little-endian byte order.
   array<Byte>^barrLE = gcnew array<Byte>(u32LE->GetByteCount( myStr ));
   u32LE->GetBytes( myStr, 0, myStr->Length, barrLE, 0 );
   
   // Get the char counts, decode eight bytes starting at index 0,
   // and print out the counts and the resulting bytes.
   Console::Write( "BE array with BE encoding : " );
   PrintCountsAndChars( barrBE, 0, 8, u32BE );
   Console::Write( "LE array with LE encoding : " );
   PrintCountsAndChars( barrLE, 0, 8, u32LE );
}

void PrintCountsAndChars( array<Byte>^bytes, int index, int count, Encoding^ enc )
{
   
   // Display the name of the encoding used.
   Console::Write( "{0,-25} :", enc );
   
   // Display the exact character count.
   int iCC = enc->GetCharCount( bytes, index, count );
   Console::Write( " {0,-3}", iCC );
   
   // Display the maximum character count.
   int iMCC = enc->GetMaxCharCount( count );
   Console::Write( " {0,-3} :", iMCC );
   
   // Decode the bytes and display the characters.
   array<Char>^chars = enc->GetChars( bytes, index, count );
   
   // The following is an alternative way to decode the bytes:
   // Char[] chars = new Char[iCC];
   // enc->GetChars( bytes, index, count, chars, 0 );
   Console::WriteLine( chars );
}

/* 
This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.

BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za

*/
using System;
using System.Text;

public class SamplesEncoding  {

   public static void Main()  {

      // Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
      Encoding u32LE = Encoding.GetEncoding( "utf-32" );
      Encoding u32BE = Encoding.GetEncoding( "utf-32BE" );

      // Use a string containing the following characters:
      //    Latin Small Letter Z (U+007A)
      //    Latin Small Letter A (U+0061)
      //    Combining Breve (U+0306)
      //    Latin Small Letter AE With Acute (U+01FD)
      //    Greek Small Letter Beta (U+03B2)
      String myStr = "za\u0306\u01FD\u03B2";

      // Encode the string using the big-endian byte order.
      byte[] barrBE = new byte[u32BE.GetByteCount( myStr )];
      u32BE.GetBytes( myStr, 0, myStr.Length, barrBE, 0 );

      // Encode the string using the little-endian byte order.
      byte[] barrLE = new byte[u32LE.GetByteCount( myStr )];
      u32LE.GetBytes( myStr, 0, myStr.Length, barrLE, 0 );

      // Get the char counts, decode eight bytes starting at index 0,
      // and print out the counts and the resulting bytes.
      Console.Write( "BE array with BE encoding : " );
      PrintCountsAndChars( barrBE, 0, 8, u32BE );
      Console.Write( "LE array with LE encoding : " );
      PrintCountsAndChars( barrLE, 0, 8, u32LE );

   }


   public static void PrintCountsAndChars( byte[] bytes, int index, int count, Encoding enc )  {

      // Display the name of the encoding used.
      Console.Write( "{0,-25} :", enc.ToString() );

      // Display the exact character count.
      int iCC  = enc.GetCharCount( bytes, index, count );
      Console.Write( " {0,-3}", iCC );

      // Display the maximum character count.
      int iMCC = enc.GetMaxCharCount( count );
      Console.Write( " {0,-3} :", iMCC );

      // Decode the bytes and display the characters.
      char[] chars = enc.GetChars( bytes, index, count );

      // The following is an alternative way to decode the bytes:
      // char[] chars = new char[iCC];
      // enc.GetChars( bytes, index, count, chars, 0 );

      Console.WriteLine( chars );

   }

}


/* 
This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.

BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za

*/

Imports System
Imports System.Text
Imports Microsoft.VisualBasic

Public Class SamplesEncoding   

   Public Shared Sub Main()

      ' Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
      Dim u32LE As Encoding = Encoding.GetEncoding("utf-32")
      Dim u32BE As Encoding = Encoding.GetEncoding("utf-32BE")

      ' Use a string containing the following characters:
      '    Latin Small Letter Z (U+007A)
      '    Latin Small Letter A (U+0061)
      '    Combining Breve (U+0306)
      '    Latin Small Letter AE With Acute (U+01FD)
      '    Greek Small Letter Beta (U+03B2)
      Dim myStr As String = "za" & ChrW(&H0306) & ChrW(&H01FD) & ChrW(&H03B2)

      ' Encode the string using the big-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates barrBE with the exact number of elements required.
      Dim barrBE(u32BE.GetByteCount(myStr) - 1) As Byte
      u32BE.GetBytes(myStr, 0, myStr.Length, barrBE, 0)

      ' Encode the string using the little-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates barrLE with the exact number of elements required.
      Dim barrLE(u32LE.GetByteCount(myStr) - 1) As Byte
      u32LE.GetBytes(myStr, 0, myStr.Length, barrLE, 0)

      ' Get the char counts, decode eight bytes starting at index 0,
      ' and print out the counts and the resulting bytes.
      Console.Write("BE array with BE encoding : ")
      PrintCountsAndChars(barrBE, 0, 8, u32BE)
      Console.Write("LE array with LE encoding : ")
      PrintCountsAndChars(barrLE, 0, 8, u32LE)

   End Sub 'Main


   Public Shared Sub PrintCountsAndChars(bytes() As Byte, index As Integer, count As Integer, enc As Encoding)

      ' Display the name of the encoding used.
      Console.Write("{0,-25} :", enc.ToString())

      ' Display the exact character count.
      Dim iCC As Integer = enc.GetCharCount(bytes, index, count)
      Console.Write(" {0,-3}", iCC)

      ' Display the maximum character count.
      Dim iMCC As Integer = enc.GetMaxCharCount(count)
      Console.Write(" {0,-3} :", iMCC)

      ' Decode the bytes.
      Dim chars As Char() = enc.GetChars(bytes, index, count)

      ' The following is an alternative way to decode the bytes:
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates the array with the exact number of elements required.
      ' Dim chars(iCC - 1) As Char
      ' enc.GetChars( bytes, index, count, chars, 0 )

      ' Display the characters.
      Console.WriteLine(chars)

   End Sub 'PrintCountsAndChars 

End Class 'SamplesEncoding


'This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.
'
'BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
'LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za

Comentarios

Encoding.GetChars Obtiene los caracteres de una secuencia de bytes de entrada.Encoding.GetChars gets characters from an input byte sequence. Encoding.GetChars es diferente de Decoder.GetChars porque Encoding espera conversiones discretas, mientras que Decoder está diseñado para varios pasos en un único flujo de entrada.Encoding.GetChars is different than Decoder.GetChars because Encoding expects discrete conversions, while Decoder is designed for multiple passes on a single input stream.

Si los datos que se va a convertir están disponibles sólo en bloques secuenciales (como los datos leídos de una secuencia) o si la cantidad de datos es tan grande que debe dividirse en bloques más pequeños, se debe usar el Decoder o Encoder proporcionada por el GetDecoder método o la GetEncoder método, respectivamente, de una clase derivada.If the data to be converted is available only in sequential blocks (such as data read from a stream) or if the amount of data is so large that it needs to be divided into smaller blocks, you should use the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively, of a derived class.

Tenga en cuenta este método está pensado para operar en caracteres Unicode, no en los datos binarios arbitrarios, como matrices de bytes.Note This method is intended to operate on Unicode characters, not on arbitrary binary data, such as byte arrays. Si tiene que codificar datos binarios arbitrarios en texto, debe usar un protocolo como uuencode, que se implementa mediante métodos como Convert.ToBase64CharArray.If you need to encode arbitrary binary data into text, you should use a protocol such as uuencode, which is implemented by methods such as Convert.ToBase64CharArray.

El GetCharCount método determina el número de caracteres resultante de descodificar una secuencia de bytes y el GetChars método realiza la descodificación real.The GetCharCount method determines how many characters result in decoding a sequence of bytes, and the GetChars method performs the actual decoding. El Encoding.GetChars método espera conversiones discretas, en contraposición al Decoder.GetChars método, que administra varios pasos en un único flujo de entrada.The Encoding.GetChars method expects discrete conversions, in contrast to the Decoder.GetChars method, which handles multiple passes on a single input stream.

Varias versiones de GetCharCount y GetChars son compatibles.Several versions of GetCharCount and GetChars are supported. Éstas son algunas consideraciones de programación para su uso de estos métodos:The following are some programming considerations for use of these methods:

  • La aplicación deba descodificar varios bytes de entrada de una página de códigos y procesar los bytes mediante varias llamadas.Your app might need to decode multiple input bytes from a code page and process the bytes using multiple calls. En este caso, probablemente necesite mantener el estado entre llamadas, porque se pueden interrumpir las secuencias de bytes cuando se procesen en lotes.In this case, you probably need to maintain state between calls, because byte sequences can be interrupted when processed in batches. (Por ejemplo, puede finalizar la parte de una secuencia de ISO-2022 MAYÚS uno GetChars llamar y continuar desde el principio del siguiente GetChars llamar.(For example, part of an ISO-2022 shift sequence may end one GetChars call and continue at the beginning of the next GetChars call. Encoding.GetChars llamará a la reserva para esas secuencias incompletas, pero Decoder recordará esas secuencias para la siguiente llamada.)Encoding.GetChars will call the fallback for those incomplete sequences, but Decoder will remember those sequences for the next call.)

  • Si la aplicación administra los resultados de la cadena, se recomienda utilizar la GetString método.If your app handles string outputs, it is recommended to use the GetString method. Dado que este método debe comprobar la longitud de cadena y asignar un búfer, es algo más lento, pero resultante String tipo es preferible.Since this method must check string length and allocate a buffer, it is slightly slower, but the resulting String type is to be preferred.

  • La versión de bytes de GetChars(Byte*, Int32, Char*, Int32) permite algunas técnicas rápidas, especialmente con varias llamadas a los búferes grandes.The byte version of GetChars(Byte*, Int32, Char*, Int32) allows some fast techniques, particularly with multiple calls to large buffers. Tenga en cuenta, sin embargo, esta versión del método a veces es segura, puesto que los punteros son necesarios.Bear in mind, however, that this method version is sometimes unsafe, since pointers are required.

  • Si la aplicación debe convertir una gran cantidad de datos, debe volver a usar el búfer de salida.If your app must convert a large amount of data, it should reuse the output buffer. En este caso, el [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29 > versión que admite caracteres de salida búferes es la mejor opción.In this case, the [], Int32, Int32, Char<xref:System.Text.Encoding.GetChars%28System.Byte%5B%5D%2CSystem.Int32%2CSystem.Int32%2CSystem.Char%5B%5D%2CSystem.Int32%29> version that supports output character buffers is the best choice.

  • Considere el uso de la Decoder.Convert método en lugar de GetCharCount.Consider using the Decoder.Convert method instead of GetCharCount. El método de conversión convierte tantos datos como sea posible y produce una excepción si el búfer de salida es demasiado pequeño.The conversion method converts as much data as possible and throws an exception if the output buffer is too small. Para la descodificación continua de un flujo, este método suele ser la mejor opción.For continuous decoding of a stream, this method is often the best choice.

Consultar también

Se aplica a