Attaching an event handler multiple times

Question

I am new to C#. I just wanted to know whether attaching event handler multiple times can cause unexpected result?

Actually in my application i am attaching an event handler to an event like

cr.ListControlPart.Grid.CurrentCellActivated += new EventHandler(Grid_CurrentCellActivated); 

and this line of code called multiple times in the code.

Answer 1

Try it yourself:

static class Program
{
    static event EventHandler MyEvent;

    static void Main()
    {
        // registering event
        MyEvent += Program_MyEvent;
        MyEvent += Program_MyEvent;
        MyEvent += Program_MyEvent;
        MyEvent += Program_MyEvent;
        MyEvent += Program_MyEvent;

        // invoke event
        MyEvent(null, EventArgs.Empty);
        Console.ReadKey();
    }

    static void Program_MyEvent(object sender, EventArgs e)
    {
        Console.WriteLine("MyEvent fired");
    }
}

Output:

MyEvent fired
MyEvent fired
MyEvent fired
MyEvent fired
MyEvent fired