This method is used in the processing page to trigger a client-side function from the server,
after the processing is over.

It is available only when the callback is made asynchronously.

You can have unlimited number of ExecOnLoad methods, and as a parameter
you can have a javascript code or the name of a javascript function.

Here is a short example:

    public string onClick(int myInt)
    {
        // ExecOnLoad examples
        ExecOnLoad("alert('some text')");
        ExecOnLoad("someCustomFunction()");
	
        // return the number received as argument multiplied by 10
        return myInt * 10;
    }
		

See also ExecOnLoad example.