. NET optional parameters and named parameters

Optional parameter, you can set the default value for the method's parameters, when the method is called, if the parameter is not passed, is to execute the default parameters.

 classProgram {Private Static voidMintx =9,strings ="A", DateTime dt =default(DateTime), GUID guid =NewGuid ()); Static voidMain (string[] args) {            //The m method will match the parameters from left to right, as follows. //GUID: Based on this name and the name in the method,//execution method equals//M (5, "A", DateTime.Now, Guid.NewGuid ());M5, Guid:Guid.NewGuid (), Dt:DateTime.Now); Console.ReadLine (); }

If the parameter requires Ref/out, in order to pass an argument in the form of a parameter name, you can use the following method:

class program     Private Static void M (refint  x) {    }         staticvoid Main (string[ ] args)        int5;             ref a);               console.readline ();        }

. NET optional parameters and named parameters