BitConverter.ToSingle Metodo

Definizione

Overload

ToSingle(ReadOnlySpan<Byte>)

Converte un intervallo di byte di sola lettura in un valore a virgola mobile e precisione doppia.Converts a read-only byte span into a double-precision floating-point value.

ToSingle(Byte[], Int32)

Restituisce un numero in virgola mobile e precisione singola convertito da quattro byte nella posizione specificata in una matrice di byte.Returns a single-precision floating point number converted from four bytes at a specified position in a byte array.

ToSingle(ReadOnlySpan<Byte>)

Converte un intervallo di byte di sola lettura in un valore a virgola mobile e precisione doppia.Converts a read-only byte span into a double-precision floating-point value.

public:
 static float ToSingle(ReadOnlySpan<System::Byte> value);
public static float ToSingle (ReadOnlySpan<byte> value);
static member ToSingle : ReadOnlySpan<byte> -> single
Public Shared Function ToSingle (value As ReadOnlySpan(Of Byte)) As Single

Parametri

value
ReadOnlySpan<Byte>

Intervallo di sola lettura contenente i byte da convertire.A read-only span containing the bytes to convert.

Restituisce

Valore a virgola mobile e precisione doppia che rappresenta i byte convertiti.A double-precision floating-point value representing the converted bytes.

Eccezioni

La lunghezza di value è minore della lunghezza di un valore Double.The length of value is less than the length of a Double value.

ToSingle(Byte[], Int32)

Restituisce un numero in virgola mobile e precisione singola convertito da quattro byte nella posizione specificata in una matrice di byte.Returns a single-precision floating point number converted from four bytes at a specified position in a byte array.

public:
 static float ToSingle(cli::array <System::Byte> ^ value, int startIndex);
public static float ToSingle (byte[] value, int startIndex);
static member ToSingle : byte[] * int -> single
Public Shared Function ToSingle (value As Byte(), startIndex As Integer) As Single

Parametri

value
Byte[]

Matrice di byte.An array of bytes.

startIndex
Int32

Posizione iniziale all'interno di value.The starting position within value.

Restituisce

Un numero in virgola mobile e precisione singola formato da quattro byte a partire da startIndex.A single-precision floating point number formed by four bytes beginning at startIndex.

Eccezioni

startIndex è maggiore o uguale alla lunghezza di value meno 3 e minore o uguale alla lunghezza di value meno 1.startIndex is greater than or equal to the length of value minus 3, and is less than or equal to the length of value minus 1.

value è null.value is null.

startIndexè minore di zero o maggiore della lunghezza di value meno 1.startIndex is less than zero or greater than the length of value minus 1.

Esempio

Nell'esempio di codice seguente gli elementi di Byte matrici vengono convertiti in Single valori con il metodo ToSingle.The following code example converts elements of Byte arrays to Single values with the ToSingle method.

// Example of the BitConverter::ToSingle method.
using namespace System;

// Convert four byte array elements to a float and display it.
void BAToSingle( array<unsigned char>^bytes, int index )
{
   float value = BitConverter::ToSingle( bytes, index );
   Console::WriteLine( "{0,5}{1,17}{2,18:E7}", index, BitConverter::ToString( bytes, index, 4 ), value );
}


// Display a byte array, using multiple lines if necessary.
void WriteMultiLineByteArray( array<unsigned char>^bytes )
{
   const int rowSize = 20;
   int iter;
   Console::WriteLine( "initial unsigned char array" );
   Console::WriteLine( "---------------------------" );
   for ( iter = 0; iter < bytes->Length - rowSize; iter += rowSize )
   {
      Console::Write( BitConverter::ToString( bytes, iter, rowSize ) );
      Console::WriteLine( "-" );

   }
   Console::WriteLine( BitConverter::ToString( bytes, iter ) );
   Console::WriteLine();
}

int main()
{
   array<unsigned char>^byteArray = {0,0,0,0,128,63,0,0,112,65,0,255,127,71,0,0,128,59,0,0,128,47,73,70,131,5,75,6,158,63,77,6,158,63,80,6,158,63,30,55,190,121,255,255,127,255,255,127,127,1,0,0,0,192,255,0,0,128,255,0,0,128,127};
   Console::WriteLine( "This example of the BitConverter::ToSingle( unsigned "
   "char[ ], int ) \nmethod generates the following output. It "
   "converts elements of a \nbyte array to float values.\n" );
   WriteMultiLineByteArray( byteArray );
   Console::WriteLine( "{0,5}{1,17}{2,18:E7}", "index", "array elements", "float" );
   Console::WriteLine( "{0,5}{1,17}{2,18:E7}", "-----", "--------------", "-----" );
   
   // Convert byte array elements to float values.
   BAToSingle( byteArray, 0 );
   BAToSingle( byteArray, 2 );
   BAToSingle( byteArray, 6 );
   BAToSingle( byteArray, 10 );
   BAToSingle( byteArray, 14 );
   BAToSingle( byteArray, 18 );
   BAToSingle( byteArray, 22 );
   BAToSingle( byteArray, 26 );
   BAToSingle( byteArray, 30 );
   BAToSingle( byteArray, 34 );
   BAToSingle( byteArray, 38 );
   BAToSingle( byteArray, 42 );
   BAToSingle( byteArray, 45 );
   BAToSingle( byteArray, 49 );
   BAToSingle( byteArray, 51 );
   BAToSingle( byteArray, 55 );
   BAToSingle( byteArray, 59 );
}

/*
This example of the BitConverter::ToSingle( unsigned char[ ], int )
method generates the following output. It converts elements of a
byte array to float values.

initial unsigned char array
---------------------------
00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
80-2F-49-46-83-05-4B-06-9E-3F-4D-06-9E-3F-50-06-9E-3F-1E-37-
BE-79-FF-FF-7F-FF-FF-7F-7F-01-00-00-00-C0-FF-00-00-80-FF-00-
00-80-7F

index   array elements             float
-----   --------------             -----
    0      00-00-00-00    0.0000000E+000
    2      00-00-80-3F    1.0000000E+000
    6      00-00-70-41    1.5000000E+001
   10      00-FF-7F-47    6.5535000E+004
   14      00-00-80-3B    3.9062500E-003
   18      00-00-80-2F    2.3283064E-010
   22      49-46-83-05    1.2345000E-035
   26      4B-06-9E-3F    1.2345671E+000
   30      4D-06-9E-3F    1.2345673E+000
   34      50-06-9E-3F    1.2345676E+000
   38      1E-37-BE-79    1.2345679E+035
   42      FF-FF-7F-FF   -3.4028235E+038
   45      FF-FF-7F-7F    3.4028235E+038
   49      01-00-00-00    1.4012985E-045
   51      00-00-C0-FF               NaN
   55      00-00-80-FF         -Infinity
   59      00-00-80-7F          Infinity
*/
// Example of the BitConverter.ToSingle method.
using System;

class BytesToSingleDemo
{
    const string formatter = "{0,5}{1,17}{2,18:E7}";
 
    // Convert four byte array elements to a float and display it.
    public static void BAToSingle( byte[ ] bytes, int index )
    {
        float value = BitConverter.ToSingle( bytes, index );

        Console.WriteLine( formatter, index, 
            BitConverter.ToString( bytes, index, 4 ), value );
    }

    // Display a byte array, using multiple lines if necessary.
    public static void WriteMultiLineByteArray( byte[ ] bytes )
    {
        const int rowSize = 20;
        int iter;

        Console.WriteLine( "initial byte array" );
        Console.WriteLine( "------------------" );

        for( iter = 0; iter < bytes.Length - rowSize; iter += rowSize )
        {
            Console.Write( 
                BitConverter.ToString( bytes, iter, rowSize ) );
            Console.WriteLine( "-" );
        }

        Console.WriteLine( BitConverter.ToString( bytes, iter ) );
        Console.WriteLine( );
    }

    public static void Main( )
    {
        byte[ ] byteArray = {
              0,   0,   0,   0, 128,  63,   0,   0, 112,  65, 
              0, 255, 127,  71,   0,   0, 128,  59,   0,   0, 
            128,  47,  73,  70, 131,   5,  75,   6, 158,  63, 
             77,   6, 158,  63,  80,   6, 158,  63,  30,  55, 
            190, 121, 255, 255, 127, 255, 255, 127, 127,   1, 
              0,   0,   0, 192, 255,   0,   0, 128, 255,   0, 
              0, 128, 127 };

        Console.WriteLine(
            "This example of the BitConverter.ToSingle( byte( ), " +
            "int ) \nmethod generates the following output. It " +
            "converts elements \nof a byte array to float values.\n" );

        WriteMultiLineByteArray( byteArray );

        Console.WriteLine( formatter, "index", "array elements", 
            "float" );
        Console.WriteLine( formatter, "-----", "--------------", 
            "-----" );
          
        // Convert byte array elements to float values.
        BAToSingle( byteArray, 0 );
        BAToSingle( byteArray, 2 );
        BAToSingle( byteArray, 6 );
        BAToSingle( byteArray, 10 );
        BAToSingle( byteArray, 14 );
        BAToSingle( byteArray, 18 );
        BAToSingle( byteArray, 22 );
        BAToSingle( byteArray, 26 );
        BAToSingle( byteArray, 30 );
        BAToSingle( byteArray, 34 );
        BAToSingle( byteArray, 38 );
        BAToSingle( byteArray, 42 );
        BAToSingle( byteArray, 45 );
        BAToSingle( byteArray, 49 );
        BAToSingle( byteArray, 51 );
        BAToSingle( byteArray, 55 );
        BAToSingle( byteArray, 59 );
    }
}

/*
This example of the BitConverter.ToSingle( byte( ), int )
method generates the following output. It converts elements
of a byte array to float values.

initial byte array
------------------
00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
80-2F-49-46-83-05-4B-06-9E-3F-4D-06-9E-3F-50-06-9E-3F-1E-37-
BE-79-FF-FF-7F-FF-FF-7F-7F-01-00-00-00-C0-FF-00-00-80-FF-00-
00-80-7F

index   array elements             float
-----   --------------             -----
    0      00-00-00-00    0.0000000E+000
    2      00-00-80-3F    1.0000000E+000
    6      00-00-70-41    1.5000000E+001
   10      00-FF-7F-47    6.5535000E+004
   14      00-00-80-3B    3.9062500E-003
   18      00-00-80-2F    2.3283064E-010
   22      49-46-83-05    1.2345000E-035
   26      4B-06-9E-3F    1.2345671E+000
   30      4D-06-9E-3F    1.2345673E+000
   34      50-06-9E-3F    1.2345676E+000
   38      1E-37-BE-79    1.2345679E+035
   42      FF-FF-7F-FF   -3.4028235E+038
   45      FF-FF-7F-7F    3.4028235E+038
   49      01-00-00-00    1.4012985E-045
   51      00-00-C0-FF               NaN
   55      00-00-80-FF         -Infinity
   59      00-00-80-7F          Infinity
*/
' Example of the BitConverter.ToSingle method.
Module BytesToSingleDemo

    Const formatter As String = "{0,5}{1,17}{2,18:E7}"
 
    ' Convert four Byte array elements to a Single and display it.
    Sub BAToSingle( bytes( ) As Byte, index As Integer )

        Dim value As Single = BitConverter.ToSingle( bytes, index )

        Console.WriteLine( formatter, index, _
            BitConverter.ToString( bytes, index, 4 ), value )
    End Sub 

    ' Display a Byte array, using multiple lines if necessary.
    Sub WriteMultiLineByteArray( bytes( ) As Byte )
       
        Const rowSize As Integer = 20 
        Dim iter As Integer

        Console.WriteLine( "initial Byte array" )
        Console.WriteLine( "------------------" )

        For iter = 0 To bytes.Length - rowSize - 1 Step rowSize
            Console.Write( _
                BitConverter.ToString( bytes, iter, rowSize ) )
            Console.WriteLine( "-" )
        Next iter

        Console.WriteLine( BitConverter.ToString( bytes, iter ) )
        Console.WriteLine( )
    End Sub

    Sub Main( )
        Dim byteArray as Byte( ) = { _
              0,   0,   0,   0, 128,  63,   0,   0, 112,  65, _
              0, 255, 127,  71,   0,   0, 128,  59,   0,   0, _
            128,  47,  73,  70, 131,   5,  75,   6, 158,  63, _
             77,   6, 158,  63,  80,   6, 158,  63,  30,  55, _
            190, 121, 255, 255, 127, 255, 255, 127, 127,   1, _
              0,   0,   0, 192, 255,   0,   0, 128, 255,   0, _
              0, 128, 127 }

        Console.WriteLine( _
            "This example of the BitConverter.ToSingle( Byte( ), " & _
            "Integer ) " & vbCrLf & "method generates the " & _
            "following output. It converts elements " & vbCrLf & _
            "of a Byte array to Single values." & vbCrLf )

        WriteMultiLineByteArray( byteArray )

        Console.WriteLine( formatter, "index", "array elements", _
            "Single" )
        Console.WriteLine( formatter, "-----", "--------------", _
            "------" )
          
        ' Convert Byte array elements to Single values.
        BAToSingle( byteArray, 0 )
        BAToSingle( byteArray, 2 )
        BAToSingle( byteArray, 6 )
        BAToSingle( byteArray, 10 )
        BAToSingle( byteArray, 14 )
        BAToSingle( byteArray, 18 )
        BAToSingle( byteArray, 22 )
        BAToSingle( byteArray, 26 )
        BAToSingle( byteArray, 30 )
        BAToSingle( byteArray, 34 )
        BAToSingle( byteArray, 38 )
        BAToSingle( byteArray, 42 )
        BAToSingle( byteArray, 45 )
        BAToSingle( byteArray, 49 )
        BAToSingle( byteArray, 51 )
        BAToSingle( byteArray, 55 )
        BAToSingle( byteArray, 59 )
    End Sub 
End Module

' This example of the BitConverter.ToSingle( Byte( ), Integer )
' method generates the following output. It converts elements
' of a Byte array to Single values.
' 
' initial Byte array
' ------------------
' 00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
' 80-2F-49-46-83-05-4B-06-9E-3F-4D-06-9E-3F-50-06-9E-3F-1E-37-
' BE-79-FF-FF-7F-FF-FF-7F-7F-01-00-00-00-C0-FF-00-00-80-FF-00-
' 00-80-7F
' 
' index   array elements            Single
' -----   --------------            ------
'     0      00-00-00-00    0.0000000E+000
'     2      00-00-80-3F    1.0000000E+000
'     6      00-00-70-41    1.5000000E+001
'    10      00-FF-7F-47    6.5535000E+004
'    14      00-00-80-3B    3.9062500E-003
'    18      00-00-80-2F    2.3283064E-010
'    22      49-46-83-05    1.2345000E-035
'    26      4B-06-9E-3F    1.2345671E+000
'    30      4D-06-9E-3F    1.2345673E+000
'    34      50-06-9E-3F    1.2345676E+000
'    38      1E-37-BE-79    1.2345679E+035
'    42      FF-FF-7F-FF   -3.4028235E+038
'    45      FF-FF-7F-7F    3.4028235E+038
'    49      01-00-00-00    1.4012985E-045
'    51      00-00-C0-FF               NaN
'    55      00-00-80-FF         -Infinity
'    59      00-00-80-7F          Infinity

Commenti

Il metodo ToSingle converte i byte da index startIndex a startIndex + 3 a un valore Single.The ToSingle method converts the bytes from index startIndex to startIndex + 3 to a Single value. L'ordine dei byte nella matrice deve riflettere la caratteristica dell'architettura del computer; Per ulteriori informazioni, vedere la sezione Osservazioni di BitConverter.The order of bytes in the array must reflect the endianness of the computer system's architecture; for more information, see the Remarks section of BitConverter.

Vedi anche

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