EncoderFallbackException Class

 

The exception that is thrown when an encoder fallback operation fails. This class cannot be inherited.

Namespace:   System.Text
Assembly:  mscorlib (in mscorlib.dll)

System::Object
  System::Exception
    System::SystemException
      System::ArgumentException
        System.Text::EncoderFallbackException

[SerializableAttribute]
public ref class EncoderFallbackException sealed : ArgumentException

NameDescription
System_CAPS_pubmethodEncoderFallbackException()

Initializes a new instance of the EncoderFallbackException class.

System_CAPS_pubmethodEncoderFallbackException(String^)

Initializes a new instance of the EncoderFallbackException class. A parameter specifies the error message.

System_CAPS_pubmethodEncoderFallbackException(String^, Exception^)

Initializes a new instance of the EncoderFallbackException class. Parameters specify the error message and the inner exception that is the cause of this exception.

NameDescription
System_CAPS_pubpropertyCharUnknown

Gets the input character that caused the exception.

System_CAPS_pubpropertyCharUnknownHigh

Gets the high component character of the surrogate pair that caused the exception.

System_CAPS_pubpropertyCharUnknownLow

Gets the low component character of the surrogate pair that caused the exception.

System_CAPS_pubpropertyData

Gets a collection of key/value pairs that provide additional user-defined information about the exception.(Inherited from Exception.)

System_CAPS_pubpropertyHelpLink

Gets or sets a link to the help file associated with this exception.(Inherited from Exception.)

System_CAPS_pubpropertyHResult

Gets or sets HRESULT, a coded numerical value that is assigned to a specific exception.(Inherited from Exception.)

System_CAPS_pubpropertyIndex

Gets the index position in the input buffer of the character that caused the exception.

System_CAPS_pubpropertyInnerException

Gets the Exception instance that caused the current exception.(Inherited from Exception.)

System_CAPS_pubpropertyMessage

Gets the error message and the parameter name, or only the error message if no parameter name is set.(Inherited from ArgumentException.)

System_CAPS_pubpropertyParamName

Gets the name of the parameter that causes this exception.(Inherited from ArgumentException.)

System_CAPS_pubpropertySource

Gets or sets the name of the application or the object that causes the error.(Inherited from Exception.)

System_CAPS_pubpropertyStackTrace

Gets a string representation of the immediate frames on the call stack.(Inherited from Exception.)

System_CAPS_pubpropertyTargetSite

Gets the method that throws the current exception.(Inherited from Exception.)

NameDescription
System_CAPS_pubmethodEquals(Object^)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethodGetBaseException()

When overridden in a derived class, returns the Exception that is the root cause of one or more subsequent exceptions.(Inherited from Exception.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetObjectData(SerializationInfo^, StreamingContext)

Sets the SerializationInfo object with the parameter name and additional exception information.(Inherited from ArgumentException.)

System_CAPS_pubmethodGetType()

Gets the runtime type of the current instance.(Inherited from Exception.)

System_CAPS_pubmethodIsUnknownSurrogate()

Indicates whether the input that caused the exception is a surrogate pair.

System_CAPS_pubmethodToString()

Creates and returns a string representation of the current exception.(Inherited from Exception.)

The following code example demonstrates the EncoderExceptionFallback and EncoderFallbackException classes.

// This example demonstrates the EncoderExceptionFallback class.

using namespace System;
using namespace System::Text;

int main()
{
    // Create an encoding, which is equivalent to calling the
    // ASCIIEncoding class constructor.
    // The EncoderExceptionFallback parameter causes an exception to
    // be thrown when a character cannot be encoded.
    // A decoder exception fallback is also specified, but it is not
    // used because this example terminates during the encoding operation.

    Encoding^ asciiEncoding = Encoding::GetEncoding("us-ascii",
        gcnew EncoderExceptionFallback(), gcnew DecoderExceptionFallback());

    // The input string consists of the Unicode characters LEFT POINTING
    // DOUBLE ANGLE QUOTATION MARK (U+00AB), 'X' (U+0058), and RIGHT
    // POINTING DOUBLE ANGLE QUOTATION MARK (U+00BB).
    // The encoding can only encode characters in the US-ASCII range of
    // U+0000 through U+007F. Consequently, the characters bracketing the
    // 'X' character cause an exception.
    String^ inputString = L"\u00abX\u00bb";

    String^ twoNewLines = Environment::NewLine + Environment::NewLine;
    array<Byte>^ encodedBytes = gcnew array<Byte>(
        asciiEncoding->GetMaxByteCount(inputString->Length));
    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);

    // ---------------------------------------------------------------------
    // Attempt to encode the input string. However, an exception is thrown
    // before the input string can be encoded.

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

    // The code example terminates during the call to the GetBytes() method.
    try
    {
        numberOfEncodedBytes = asciiEncoding->GetBytes(inputString, 0,
            inputString->Length, encodedBytes, 0);
        // This statement is never executed.
        Console::WriteLine("This statement is never executed.");
    }
    catch (EncoderFallbackException^ 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): "X"
Input string in hexadecimal: 0xAB 0x58 0xBB

Encode the input string...
System.Text.EncoderFallbackException: Unable to translate Unicode character \u00AB at inde
x 0 to specified code page.
at System.Text.EncoderExceptionFallbackBuffer.Fallback(Char charUnknown, Int32 index)
at System.Text.EncoderFallbackBuffer.InternalFallback(Char ch, Char*& chars)
at System.Text.ASCIIEncoding.GetBytes(Char* chars, Int32 charCount, Byte* bytes, Int32
byteCount, EncoderNLS encoder)
at System.Text.ASCIIEncoding.GetBytes(String chars, Int32 charIndex, Int32 charCount, B
yte[] bytes, Int32 byteIndex)
at Sample.Main()

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

*/

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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