Set the FieldSpecified property automatically in WSDL generated files

If you use the nillable or minOccurs attributes in the WSDL files, the wsdl.exe tool generates a boolean 'Specified' field. In order to transmit the field value, this field must be set 'true' even if a value is assigned to the field. This post shows how to automatically add code to set the Specified property in WSDL generated files.