Fire Event problem

Question

I would like to manually fire a SizeChangedEvent, but having problems to get it fired.
I get Invalid arguments error, when trying to call it.
Here is my code:
private delegate void ChangedDelegate(object sender, SizeChangedEventArgs e);
private event ChangedDelegate ChangedEvent;
public void MyMethod(string str)
        //do stuff ....
        //Manually Raise event here
        ChangedEvent(this, SizeChangedEventArgs.Empty);        //get error: some Invalid arguments  
//standard method sizechanged
private void Control_SizeChanged(object sender, SizeChangedEventArgs e)
        //do stuff ....  
Any help and explanation appriciated.
Thanks

Answer 1

The SizeChangedEventArgs.Empty property returns an EventArgs (though the EventArgs base class) and and EventArgs cannot be casted to a SizeChangedEventArgs.
In fact the SizeChangedEventArgs class doesn't have any public constructor so you cannot create an instance of it nor manually invoke the event.
If you want to run some code inside the SizeChanged event handler, you should move this code to a method and then call this method directly from the event handler and your MyMethod:
public void MyMethod(string str) {
//do stuff ....
DoStuff();
private void Control_SizeChanged(object sender, SizeChangedEventArgs e) {
DoStuff();
private void DoStuff() {
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