Func delegate with no return type

Question

All of the Func delegates return a value  What are the  NET delegates that can be used with methods that return void

User · Answer

Try System Func lt T gt  and System Action

User · Answer

All Func delegates return something  all the Action delegates return void   Func lt TResult gt  takes no arguments and returns TResult   public delegate TResult Func lt TResult gt      Action lt T gt  takes one argument and does not return a value   public delegate void Action lt T gt  T obj    Action is the simplest   bare  delegate   public delegate void Action     There s also Func lt TArg1  TResult gt  and Action lt TArg1  TArg2 gt   and others up to 16 arguments   All of these  except for Action lt T gt   are new to  NET 3 5  defined in System Core

User · Answer

takes no arguments and has a void return type    I believe Action is a solution to this

User · Answer

All of the Func delegates take at least one parameter   That s not true   They all take at least one type argument  but that argument determines the return type    So Func lt T gt  accepts no parameters and returns a value   Use Action or Action lt T gt  when you don t want to return a value

User · Answer

A very easy way to invoke return and non return value subroutines  is using Func and Action respectively   see also https   msdn microsoft com en-us library 018hxwa8 v vs 110  aspx    Try this this example  using System   public class Program       private Func lt string string gt  FunctionPTR   null        private Func lt string string  string gt  FunctionPTR1   null        private Action lt object gt  ProcedurePTR   null          private string Display string message                    Console WriteLine message             return null                 private string Display string message1 string message2                    Console WriteLine message1             Console WriteLine message2             return null                 public void ObjectProcess object param                if  param    null                        throw new ArgumentNullException  Parameter is null or missing                      else                        Console WriteLine  Object is valid                          public void Main string   args                    FunctionPTR   Display            FunctionPTR1  Display            ProcedurePTR   ObjectProcess          FunctionPTR  Welcome to function pointer sample               FunctionPTR1  Welcome   This is function pointer sample               ProcedurePTR new object

User · Answer

takes no arguments and has a void return type    If you are writing for System Windows Forms  You can also use    public delegate void MethodInvoker

User · Answer

Occasionally you will want to write a delegate for event handling  in which case you can take advantage of System EvenHandler lt T gt  which implicitly accepts an argument of type object in addition to the second parameter that should derive from EventArgs  EventHandlers will return void  I personally found this useful during testing for creating a one-off callback in a function body

[c#] Func delegate with no return type

Examples related to c#

Examples related to .net