When overridden in a derived class, retrieves the next character in the fallback buffer.
Assembly: mscorlib (in mscorlib.dll)
An encoding operation calls the Fallback method if the operation encounters an unknown character or surrogate pair in the input. For example, in the case of a replacement fallback, if the Fallback method returns true, a substitute string exists that can be encoded instead of the unknown input. The encoding operation calls the method repeatedly and obtains the substitute string one character at a time. When all characters in the fallback buffer have been returned to the encoder, the method should return U+0000.
For an exception fallback handler, the method should return U+0000.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.