C# Online Compiler | .NET Fiddle

<no name> by Anonymous

using System;

public class Program
{
	public static void Main()
	{
		int x = 5;
		x.Extend();
		dynamic y = x;
		y.Extend();
	}
}

static class Foo
{
	public static void Extend(this int x){
		Console.WriteLine(x);
	}
}

​x
 
using System;
​
public class Program
{
    public static void Main()
    {
        int x = 5;
        x.Extend();
        dynamic y = x;
        y.Extend();
    }
}
​
static class Foo
{
    public static void Extend(this int x){
        Console.WriteLine(x);
    }
}

5
Run-time exception (line -1): 'int' does not contain a definition for 'Extend'

Stack Trace:

[Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: 'int' does not contain a definition for 'Extend']
   at CallSite.Target(Closure , CallSite , Object )
   at System.Dynamic.UpdateDelegates.UpdateAndExecuteVoid1[T0](CallSite site, T0 arg0)
   at Program.Main()

Last Run:	3:32:59 am
Compile:	0.127s
Execute:	0.016s
Memory:	162.05kb
CPU:	0.062s

View IL Code