DecoderFallbackException クラス
定義
重要
一部の情報は、リリース前に大きく変更される可能性があるプレリリースされた製品に関するものです。 Microsoft は、ここに記載されている情報について、明示または黙示を問わず、一切保証しません。
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。 このクラスは継承できません。
public ref class DecoderFallbackException sealed : ArgumentExceptionpublic sealed class DecoderFallbackException : ArgumentException[System.Serializable]
public sealed class DecoderFallbackException : ArgumentExceptiontype DecoderFallbackException = class
inherit ArgumentException[<System.Serializable>]
type DecoderFallbackException = class
inherit ArgumentExceptionPublic NotInheritable Class DecoderFallbackException
Inherits ArgumentException- 継承
- 継承
- 属性
例
次のコード例では、 クラスと DecoderFallbackException クラスをDecoderExceptionFallback示します。
// 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.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
End Class
'
'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 クラスの新しいインスタンスを初期化します。 |
| DecoderFallbackException(String) |
DecoderFallbackException クラスの新しいインスタンスを初期化します。 パラメーターでは、エラー メッセージを指定します。 |
| 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。 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。 |
| DecoderFallbackException(String, Exception) |
DecoderFallbackException クラスの新しいインスタンスを初期化します。 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。 |
プロパティ
| 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。 |
| Data |
例外に関する追加のユーザー定義情報を提供する、キーと値のペアのコレクションを取得します。 (継承元 Exception) |
| 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。 (継承元 Exception) |
| 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。 (継承元 Exception) |
| 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。 |
| 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。 (継承元 Exception) |
| 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。 (継承元 ArgumentException) |
| ParamName |
この例外の原因である引数の名前を取得します。 (継承元 ArgumentException) |
| 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。 (継承元 Exception) |
| 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。 (継承元 Exception) |
| TargetSite |
現在の例外がスローされたメソッドを取得します。 (継承元 Exception) |
メソッド
| Equals(Object) |
指定され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。 (継承元 Object) |
| 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 つ以上の例外の根本原因である Exception を返します。 (継承元 Exception) |
| GetHashCode() |
既定のハッシュ関数として機能します。 (継承元 Object) |
| 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。 (継承元 ArgumentException) |
| GetType() |
現在のインスタンスのランタイム型を取得します。 (継承元 Exception) |
| MemberwiseClone() |
現在の Object の簡易コピーを作成します。 (継承元 Object) |
| ToString() |
現在の例外の文字列形式を作成して返します。 (継承元 Exception) |
イベント
| SerializeObjectState |
古い.
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。 (継承元 Exception) |