An encrypted code used to authenticate the request and response, for example, "DV+TpDfx1/TdSE9ktyK9k/bDTVI=". Only use this value is you
            want to create the signature file yourself. Generally you should use the SignatureFileContents value.
             
            
 Declaration Syntax
 Declaration Syntax| C# | 
public string SignatureFileContents { get; set; }