DecoderFallbackException DecoderFallbackException DecoderFallbackException DecoderFallbackException Class

定義

デコーダー フォールバック操作が失敗したときにスローされる例外。The exception that is thrown when a decoder fallback operation fails. このクラスは継承できません。This class cannot be inherited.

public ref class DecoderFallbackException sealed : ArgumentException
[System.Serializable]
public sealed class DecoderFallbackException : ArgumentException
type DecoderFallbackException = class
    inherit ArgumentException
Public NotInheritable Class DecoderFallbackException
Inherits ArgumentException
継承
属性

次のコード例に示します、DecoderExceptionFallbackDecoderFallbackExceptionクラス。The following code example demonstrates the DecoderExceptionFallback and DecoderFallbackException classes.

// This example demonstrates the DecoderExceptionFallback class.

using namespace System;
using namespace System::Text;

int main()
{
    // Create an encoding, which is equivalent to calling the
    // ASCIIEncoding class constructor.
    // The DecoderExceptionFallback parameter specifies that an exception
    // is thrown if a character cannot be encoded.
    // An encoder exception fallback is also specified, but in this code
    // example the encoding operation cannot fail.

    Encoding^ asciiEncoding = Encoding::GetEncoding("us-ascii",
        gcnew EncoderExceptionFallback(), gcnew DecoderExceptionFallback());
    String^ inputString = "XYZ";
    String^ decodedString;
    String^ twoNewLines = Environment::NewLine + Environment::NewLine ;

    array<Byte>^ encodedBytes = 
        gcnew array<Byte>(asciiEncoding->GetByteCount(inputString));
    int numberOfEncodedBytes = 0;

    // ---------------------------------------------------------------------
    Console::Clear();

    // Display the name of the encoding.
    Console::WriteLine("The name of the encoding is \"{0}\".{1}",
        asciiEncoding->WebName, Environment::NewLine);

    // Display the input string in text.
    Console::WriteLine("Input string ({0} characters): \"{1}\"",
        inputString->Length, inputString);

    // Display the input string in hexadecimal.
    Console::Write("Input string in hexadecimal: ");
    for each (char c in inputString)
    {
        Console::Write("0x{0:X2} ", c);
    }
    Console::Write(twoNewLines);

    // ---------------------------------------------------------------------
    // Encode the input string.

    Console::WriteLine("Encode the input string...");

    numberOfEncodedBytes = asciiEncoding->GetBytes(inputString, 0,
        inputString->Length, encodedBytes, 0);

    // Display the encoded bytes.
    Console::WriteLine("Encoded bytes in hexadecimal ({0} bytes):{1}",
        numberOfEncodedBytes, Environment::NewLine);
    for each (Byte b in encodedBytes)
    {
        Console::Write("0x{0:X2} ", b);
    }
    Console::Write(twoNewLines);

    // ---------------------------------------------------------------------

    // Replace the encoded byte sequences for the characters 'X' and 'Z'
    // with the value 0xFF, which is outside the valid range of 0x00 to 0x7F
    // for ASCIIEncoding. The resulting byte sequence is actually the
    // beginning of this code example because it is the input to the decoder
    // operation, and is equivalent to a corrupted or improperly encoded
    // byte sequence.

    encodedBytes[0] = 0xFF;
    encodedBytes[2] = 0xFF;

    Console::WriteLine("Display the corrupted byte sequence...");
    Console::WriteLine("Encoded bytes in hexadecimal ({0} bytes):{1}",
        numberOfEncodedBytes, Environment::NewLine);
    for each (Byte b in encodedBytes)
    {
        Console::Write("0x{0:X2} ", b);
    }
    Console::Write(twoNewLines);

    // ---------------------------------------------------------------------
    // Attempt to decode the encoded bytes. However, an exception is thrown
    // before the byte sequence can be decoded.

    Console::WriteLine("Compare the decoded bytes to the input string...");

    try
    {
        decodedString = asciiEncoding->GetString(encodedBytes);
        // This statement is never executed.
        Console::WriteLine("This statement is never executed.");
    }
    catch (DecoderFallbackException^ ex)
    {
        Console::WriteLine(ex);
        Console::WriteLine(
            "{0}*** THE CODE EXAMPLE TERMINATES HERE AS INTENDED. ***", 
            Environment::NewLine);
    }
}


/*
This code example produces the following results:

The name of the encoding is "us-ascii".

Input string (3 characters): "XYZ"
Input string in hexadecimal: 0x58 0x59 0x5A

Encode the input string...
Encoded bytes in hexadecimal (3 bytes):

0x58 0x59 0x5A

Display the corrupted byte sequence...
Encoded bytes in hexadecimal (3 bytes):

0xFF 0x59 0xFF

Compare the decoded bytes to the input string...
System.Text.DecoderFallbackException: Unable to translate bytes [FF] at index 0 from speci
fied code page to Unicode.
at System.Text.DecoderExceptionFallbackBuffer.Throw(Byte[] bytesUnknown, Int32 index)
at System.Text.DecoderExceptionFallbackBuffer.Fallback(Byte[] bytesUnknown, Int32 index
)
at System.Text.DecoderFallbackBuffer.InternalFallback(Byte[] bytes, Byte* pBytes)
at System.Text.ASCIIEncoding.GetCharCount(Byte* bytes, Int32 count, DecoderNLS decoder)

at System.String.CreateStringFromEncoding(Byte* bytes, Int32 byteLength, Encoding encod
ing)
at System.Text.ASCIIEncoding.GetString(Byte[] bytes, Int32 byteIndex, Int32 byteCount)
at System.Text.Encoding.GetString(Byte[] bytes)
at Sample.Main()

*** THE CODE EXAMPLE TERMINATES HERE AS INTENDED. ***

*/
// This example demonstrates the DecoderExceptionFallback class.

using System;
using System.Text;

class Sample 
{
    public static void Main() 
    {

// Create an encoding, which is equivalent to calling the 
// ASCIIEncoding class constructor. 
// The DecoderExceptionFallback parameter specifies that an exception
// is thrown if a character cannot be encoded. 
// An encoder exception fallback is also specified, but in this code
// example the encoding operation cannot fail.  

    Encoding ae = Encoding.GetEncoding(
                  "us-ascii",
                  new EncoderExceptionFallback(), 
                  new DecoderExceptionFallback());
    string inputString = "XYZ";
    string decodedString;
    string twoNewLines = "\n\n";
    byte[] encodedBytes = new byte[ae.GetByteCount(inputString)];
    int numberOfEncodedBytes = 0;

// --------------------------------------------------------------------------
    Console.Clear();

// Display the name of the encoding.
    Console.WriteLine("The name of the encoding is \"{0}\".\n", ae.WebName);

// Display the input string in text.
    Console.WriteLine("Input string ({0} characters): \"{1}\"", 
                       inputString.Length, inputString);

// Display the input string in hexadecimal.
    Console.Write("Input string in hexadecimal: ");
    foreach (char c in inputString.ToCharArray()) 
        {
        Console.Write("0x{0:X2} ", (int)c);
        }
    Console.Write(twoNewLines);

// --------------------------------------------------------------------------
// Encode the input string. 

    Console.WriteLine("Encode the input string...");
    numberOfEncodedBytes = ae.GetBytes(inputString, 0, inputString.Length, 
                                       encodedBytes, 0);
// Display the encoded bytes.
    Console.WriteLine("Encoded bytes in hexadecimal ({0} bytes):\n", 
                       numberOfEncodedBytes);
    foreach (byte b in encodedBytes)
        {
        Console.Write("0x{0:X2} ", (int)b);
        }
    Console.Write(twoNewLines);

// --------------------------------------------------------------------------

// Replace the encoded byte sequences for the characters 'X' and 'Z' with the 
// value 0xFF, which is outside the valid range of 0x00 to 0x7F for 
// ASCIIEncoding. The resulting byte sequence is actually the beginning of 
// this code example because it is the input to the decoder operation, and 
// is equivalent to a corrupted or improperly encoded byte sequence. 

    encodedBytes[0] = 0xFF;
    encodedBytes[2] = 0xFF;

    Console.WriteLine("Display the corrupted byte sequence...");
    Console.WriteLine("Encoded bytes in hexadecimal ({0} bytes):\n", 
                       numberOfEncodedBytes);
    foreach (byte b in encodedBytes)
        {
        Console.Write("0x{0:X2} ", (int)b);
        }
    Console.Write(twoNewLines);

// --------------------------------------------------------------------------
// Attempt to decode the encoded bytes. However, an exception is thrown 
// before the byte sequence can be decoded.

    Console.WriteLine("Compare the decoded bytes to the input string...");

    try {
        decodedString = ae.GetString(encodedBytes);
        }
    catch (DecoderFallbackException dfe)
        {
        Console.WriteLine(dfe);
        Console.WriteLine("\n*** THE CODE EXAMPLE TERMINATES HERE AS INTENDED. ***");
        return;
        }

// This statement is never executed.
    Console.WriteLine("This statement is never executed.");
    }
}
/*
This code example produces the following results:

The name of the encoding is "us-ascii".

Input string (3 characters): "XYZ"
Input string in hexadecimal: 0x58 0x59 0x5A

Encode the input string...
Encoded bytes in hexadecimal (3 bytes):

0x58 0x59 0x5A

Display the corrupted byte sequence...
Encoded bytes in hexadecimal (3 bytes):

0xFF 0x59 0xFF

Compare the decoded bytes to the input string...
System.Text.DecoderFallbackException: Unable to translate bytes [FF] at index 0 from speci
fied code page to Unicode.
   at System.Text.DecoderExceptionFallbackBuffer.Throw(Byte[] bytesUnknown, Int32 index)
   at System.Text.DecoderExceptionFallbackBuffer.Fallback(Byte[] bytesUnknown, Int32 index
)
   at System.Text.DecoderFallbackBuffer.InternalFallback(Byte[] bytes, Byte* pBytes)
   at System.Text.ASCIIEncoding.GetCharCount(Byte* bytes, Int32 count, DecoderNLS decoder)

   at System.String.CreateStringFromEncoding(Byte* bytes, Int32 byteLength, Encoding encod
ing)
   at System.Text.ASCIIEncoding.GetString(Byte[] bytes, Int32 byteIndex, Int32 byteCount)
   at System.Text.Encoding.GetString(Byte[] bytes)
   at Sample.Main()

*** THE CODE EXAMPLE TERMINATES HERE AS INTENDED. ***

*/
' This example demonstrates the DecoderExceptionFallback class.
Imports System
Imports System.Text

Class Sample
    Public Shared Sub Main() 
        
        ' Create an encoding, which is equivalent to calling the 
        ' ASCIIEncoding class constructor. 
        ' The DecoderExceptionFallback parameter specifies that an exception
        ' is thrown if a character cannot be encoded. 
        ' An encoder exception fallback is also specified, but in this code
        ' example the encoding operation cannot fail.  


        Dim eef As New EncoderExceptionFallback()
        Dim def As New DecoderExceptionFallback()
        Dim ae As Encoding = Encoding.GetEncoding("us-ascii", eef, def)
        Dim inputString As String = "XYZ"
        Dim decodedString As String
        Dim twoNewLines As String = vbCrLf & vbCrLf
        Dim numberOfEncodedBytes As Integer = ae.GetByteCount(inputString)
        ' Counteract the compiler adding an extra element.
        Dim encodedBytes(numberOfEncodedBytes - 1) As Byte
        
        ' --------------------------------------------------------------------------
        Console.Clear()
        
        ' Display the name of the encoding.
        Console.WriteLine("The name of the encoding is ""{0}""." & vbCrLf, ae.WebName)
        
        ' Display the input string in text.
        Console.WriteLine("Input string ({0} characters): ""{1}""", inputString.Length, inputString)
        
        ' Display the input string in hexadecimal.
        ' Each element is converted to an integer with Convert.ToInt32.
        Console.Write("Input string in hexadecimal: ")
        Dim c As Char
        For Each c In  inputString.ToCharArray()
            Console.Write("0x{0:X2} ", Convert.ToInt32(c))
        Next c
        Console.Write(twoNewLines)
        
        ' --------------------------------------------------------------------------
        ' Encode the input string. 
        Console.WriteLine("Encode the input string...")
        numberOfEncodedBytes = ae.GetBytes(inputString, 0, inputString.Length, _
                                           encodedBytes, 0)
        ' Display the encoded bytes.
        ' Each element is converted to an integer with Convert.ToInt32.
        Console.WriteLine("Encoded bytes in hexadecimal ({0} bytes):" & vbCrLf, _
                           numberOfEncodedBytes)
        Dim b As Byte
        For Each b In  encodedBytes
            Console.Write("0x{0:X2} ", Convert.ToInt32(b))
        Next b
        Console.Write(twoNewLines)
        
        ' --------------------------------------------------------------------------
        ' Replace the encoded byte sequences for the characters 'X' and 'Z' with the 
        ' value 0xFF, which is outside the valid range of 0x00 to 0x7F for 
        ' ASCIIEncoding. The resulting byte sequence is actually the beginning of 
        ' this code example because it is the input to the decoder operation, and 
        ' is equivalent to a corrupted or improperly encoded byte sequence. 

        encodedBytes(0) = &HFF
        encodedBytes(2) = &HFF
        
        Console.WriteLine("Display the corrupted byte sequence...")
        ' Each element is converted to an integer with Convert.ToInt32.
        Console.WriteLine("Encoded bytes in hexadecimal ({0} bytes):" & vbCrLf, _
                           numberOfEncodedBytes)
        For Each b In  encodedBytes
            Console.Write("0x{0:X2} ", Convert.ToInt32(b))
        Next b
        Console.Write(twoNewLines)
        
        ' --------------------------------------------------------------------------
        ' Attempt to decode the encoded bytes. However, an exception is thrown 
        ' before the byte sequence can be decoded.
        Console.WriteLine("Compare the decoded bytes to the input string...")
        
        Try
            decodedString = ae.GetString(encodedBytes)
        Catch dfe As DecoderFallbackException
            Console.WriteLine(dfe)
            Console.WriteLine(vbCrLf & _
                              "*** THE CODE EXAMPLE TERMINATES HERE AS INTENDED. ***")
            Return
        End Try
        
        ' This statement is never executed.
        Console.WriteLine("This statement is never executed.")
    
    End Sub 'Main
End Class 'Sample
'
'This code example produces the following results:
'
'The name of the encoding is "us-ascii".
'
'Input string (3 characters): "XYZ"
'Input string in hexadecimal: 0x58 0x59 0x5A
'
'Encode the input string...
'Encoded bytes in hexadecimal (3 bytes):
'
'0x58 0x59 0x5A
'
'Display the corrupted byte sequence...
'Encoded bytes in hexadecimal (3 bytes):
'
'0xFF 0x59 0xFF
'
'Compare the decoded bytes to the input string...
'System.Text.DecoderFallbackException: Unable to translate bytes [FF] at index 0 from speci
'fied code page to Unicode.
'   at System.Text.DecoderExceptionFallbackBuffer.Throw(Byte[] bytesUnknown, Int32 index)
'   at System.Text.DecoderExceptionFallbackBuffer.Fallback(Byte[] bytesUnknown, Int32 index
')
'   at System.Text.DecoderFallbackBuffer.InternalFallback(Byte[] bytes, Byte* pBytes)
'   at System.Text.ASCIIEncoding.GetCharCount(Byte* bytes, Int32 count, DecoderNLS decoder)
'
'   at System.String.CreateStringFromEncoding(Byte* bytes, Int32 byteLength, Encoding encod
'ing)
'   at System.Text.ASCIIEncoding.GetString(Byte[] bytes, Int32 byteIndex, Int32 byteCount)
'   at System.Text.Encoding.GetString(Byte[] bytes)
'   at Sample.Main()
'
'*** THE CODE EXAMPLE TERMINATES HERE AS INTENDED. ***
'
'

コンストラクター

DecoderFallbackException() DecoderFallbackException() DecoderFallbackException() DecoderFallbackException()

DecoderFallbackException クラスの新しいインスタンスを初期化します。Initializes a new instance of the DecoderFallbackException class.

DecoderFallbackException(String) DecoderFallbackException(String) DecoderFallbackException(String) DecoderFallbackException(String)

DecoderFallbackException クラスの新しいインスタンスを初期化します。Initializes a new instance of the DecoderFallbackException class. パラメーターでは、エラー メッセージを指定します。A parameter specifies the error message.

DecoderFallbackException(String, Byte[], Int32) DecoderFallbackException(String, Byte[], Int32) DecoderFallbackException(String, Byte[], Int32) DecoderFallbackException(String, Byte[], Int32)

DecoderFallbackException クラスの新しいインスタンスを初期化します。Initializes a new instance of the DecoderFallbackException class. パラメーターでは、エラー メッセージ、デコードするバイト配列、およびデコードできないバイトのインデックスを指定します。Parameters specify the error message, the array of bytes being decoded, and the index of the byte that cannot be decoded.

DecoderFallbackException(String, Exception) DecoderFallbackException(String, Exception) DecoderFallbackException(String, Exception) DecoderFallbackException(String, Exception)

DecoderFallbackException クラスの新しいインスタンスを初期化します。Initializes a new instance of the DecoderFallbackException class. パラメーターでは、エラー メッセージと、この例外の原因となった内部例外を指定します。Parameters specify the error message and the inner exception that is the cause of this exception.

プロパティ

BytesUnknown BytesUnknown BytesUnknown BytesUnknown

例外の原因となった入力バイト シーケンスを取得します。Gets the input byte sequence that caused the exception.

Data Data Data Data

例外に関する追加のユーザー定義情報を提供する、キー/値ペアのコレクションを取得します。Gets a collection of key/value pairs that provide additional user-defined information about the exception.

(Inherited from Exception)
HelpLink HelpLink HelpLink HelpLink

この例外に関連付けられているヘルプ ファイルへのリンクを取得または設定します。Gets or sets a link to the help file associated with this exception.

(Inherited from Exception)
HResult HResult HResult HResult

特定の例外に割り当てられているコード化数値である HRESULT を取得または設定します。Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception.

(Inherited from Exception)
Index Index Index Index

例外の原因となったバイトの入力バイト シーケンスにおけるインデックス位置を取得します。Gets the index position in the input byte sequence of the byte that caused the exception.

InnerException InnerException InnerException InnerException

現在の例外の原因となる Exception インスタンスを取得します。Gets the Exception instance that caused the current exception.

(Inherited from Exception)
Message Message Message Message

エラー メッセージとパラメーター名を取得します。パラメーター名が設定されていない場合は、エラー メッセージだけを取得します。Gets the error message and the parameter name, or only the error message if no parameter name is set.

(Inherited from ArgumentException)
ParamName ParamName ParamName ParamName

この例外の原因である引数の名前を取得します。Gets the name of the parameter that causes this exception.

(Inherited from ArgumentException)
Source Source Source Source

エラーの原因となるアプリケーションまたはオブジェクトの名前を取得または設定します。Gets or sets the name of the application or the object that causes the error.

(Inherited from Exception)
StackTrace StackTrace StackTrace StackTrace

呼び出し履歴で直前のフレームの文字列形式を取得します。Gets a string representation of the immediate frames on the call stack.

(Inherited from Exception)
TargetSite TargetSite TargetSite TargetSite

現在の例外がスローされたメソッドを取得します。Gets the method that throws the current exception.

(Inherited from Exception)

メソッド

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

指定したオブジェクトが、現在のオブジェクトと等しいかどうかを判断します。Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetBaseException() GetBaseException() GetBaseException() GetBaseException()

派生クラスでオーバーライドされた場合、それ以後に発生する 1 つ以上の例外の主要な原因である Exception を返します。When overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions.

(Inherited from Exception)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

既定のハッシュ関数として機能します。Serves as the default hash function.

(Inherited from Object)
GetObjectData(SerializationInfo, StreamingContext) GetObjectData(SerializationInfo, StreamingContext) GetObjectData(SerializationInfo, StreamingContext) GetObjectData(SerializationInfo, StreamingContext)

パラメーター名と追加の例外情報を使用して SerializationInfo オブジェクトを設定します。Sets the SerializationInfo object with the parameter name and additional exception information.

(Inherited from ArgumentException)
GetType() GetType() GetType() GetType()

現在のインスタンスのランタイム型を取得します。Gets the runtime type of the current instance.

(Inherited from Exception)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

現在の Object の簡易コピーを作成します。Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

現在の例外の文字列形式を作成して返します。Creates and returns a string representation of the current exception.

(Inherited from Exception)

イベント

SerializeObjectState SerializeObjectState SerializeObjectState SerializeObjectState

例外がシリアル化され、例外に関するシリアル化されたデータを含む例外状態オブジェクトが作成されたときに発生します。Occurs when an exception is serialized to create an exception state object that contains serialized data about the exception.

(Inherited from Exception)

適用対象

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