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DecoderReplacementFallback Class

Provides a failure-handling mechanism, called a fallback, for an encoded input byte sequence that cannot be converted to an output character. The fallback emits a user-specified replacement string instead of a decoded input byte sequence. This class cannot be inherited.


Namespace:  System.Text
Assemblies:   System.Text.Encoding (in System.Text.Encoding.dll)
  mscorlib (in mscorlib.dll)

type DecoderReplacementFallback =  
        inherit DecoderFallback 

The DecoderReplacementFallback type exposes the following members.

Public methodDecoderReplacementFallback()Initializes a new instance of the DecoderReplacementFallback class.
Public methodDecoderReplacementFallback(String)Initializes a new instance of the DecoderReplacementFallback class using a specified replacement string.

Public propertyDefaultStringGets the replacement string that is the value of the DecoderReplacementFallback object.
Public propertyMaxCharCountGets the number of characters in the replacement string for the DecoderReplacementFallback object. (Overrides DecoderFallback.MaxCharCount.)

Public methodCreateFallbackBufferCreates a DecoderFallbackBuffer object that is initialized with the replacement string of this DecoderReplacementFallback object. (Overrides DecoderFallback.CreateFallbackBuffer().)
Public methodEqualsIndicates whether the value of a specified object is equal to the DecoderReplacementFallback object. (Overrides Object.Equals(Object).)
Public methodGetHashCodeRetrieves the hash code for the value of the DecoderReplacementFallback object. (Overrides Object.GetHashCode().)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

A common reason for an encoding or decoding operation to fail is if the underlying encoding class does not provide a mapping between a character and an equivalent byte sequence. For example, an ASCIIEncoding object cannot decode a byte value greater than 0x7F. If an input byte sequence cannot be converted to an output character, a DecoderReplacementFallback object emits a replacement string into the output to represent the original input byte sequence. The conversion process then continues to decode the remainder of the original input.

The replacement string used by a DecoderReplacementFallback object is determined by the call to its class constructor. Two options are available:

This class is one of two .NET Framework classes that implement different fallback strategies for handling decoding conversion failures. The other class is the DecoderExceptionFallback class, which throws a DecoderFallbackException when an invalid byte sequence is encountered.

The following code example demonstrates the DecoderReplacementFallback class.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

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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