The best overloaded method match for System.Threading.Timer.Timer() has some invalid arguments

Question

I'm making a console application that must call a certain method in timed intervals.

I've searched for that and found that the System.Threading.Timer class can achieve such a functionality, but I'm not quite following how to implement it.

I tried this:

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; using System.Threading; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { Timer x = new Timer(test, null, 0, 1000); Console.ReadLine(); } public static void test() { Console.WriteLine("test"); } } }

But I get an error on the Timer x = new Timer(test, null, 0, 1000); line that says:

The best overloaded method match for System.Threading.Timer.Timer(System.Threading.TimerCallback, object, int, int)' has some invalid arguments

I really don't know how to make this work properly, but if anyone has a link or something that can explain timers for a beginner, I'd be grateful.

msdn.microsoft.com/en-us/library/… not sure he will understand lambda's but Jon's Answer is spot on.. msdn.microsoft.com/en-us/library /system.threading.timercallback.aspx stackoverflow.com/questions/1416803/… — MethodMan
– MethodMan, Commented Dec 23, 2012 at 14:50

Jon Skeet · Accepted Answer · 2012-12-23 14:58:15Z

The problem is that the signature of your test() method:

public static void test()

doesn't match the required signature for TimerCallback:

public delegate void TimerCallback( Object state )

That means you can't create a TimerCallback directly from the test method. The simplest thing to do is to change the signature of your test method:

public static void test(Object state)

Or you could use a lambda expression in your constructor call:

Timer x = new Timer(state => test(), null, 0, 1000);

Note that to follow .NET naming conventions, your method name should start with a capital letter, e.g. Test rather than test.

That worked. Thanks. But may you provide me with links that talk about delegates, so i can understand what's it all about ?

Tom · Accepted Answer · 2012-12-23 14:55:51Z

TimerCallback delegate (first argument of the Timer constructor you use) takes one argument (state) of type object.

All you have to do it to add parameter to the test method

public static void test(object state) { Console.WriteLine("test"); }

And the issue will be resolved.

Rashedul.Rubel · Accepted Answer · 2012-12-23 19:14:45Z

write the test method as follows to resolve the exception:

public static void test(object state) { Console.WriteLine("test"); }

Collectives™ on Stack Overflow

The best overloaded method match for System.Threading.Timer.Timer() has some invalid arguments

3 Answers 3

1 Comment

Comments

Comments

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

Comments

Linked

Related