Enables or disables the throwing of an exception on an unmappable Unicode character that is converted to an ANSI "?" character.
The UnmanagedFunctionPointerAttribute.ThrowOnUnmappableChar field is false by default, which means that the field is disabled. Set this field to true to indicate that an exception is thrown each time the interop marshaler converts an unmappable character.
For more information, see DllImportAttribute.ThrowOnUnmappableChar.