How to subscribe an event from UserControl with Additional parameters?

sasikumar

Hi,

I've a form frmMain.cs, in which I've added a UserControl ucTest.cs. In the usercontrol, I've added a button click event, in which I'm populating a DataSet ds.

Now I need this dataset to be used on the frmMain.cs for manipulation. How do I pass the dataset ds which was updated in the click event of UserControl back to the frmMain.cs ?

I tried declare a delegate (i'm totally new to delegates) in the UserControl for this, as below --

public delegate Boolean EventHandler(object sender, EventArgs args, DataSet ds);
public event EventHandler evntExecute = delegate {};

In the frmMain.cs, I've added a EventHandler function as below --

public Boolean evntExecute_Handler(object sender, EventArgs e, DataSet ds)
{
// code using the Dataset ds values
}

Now how do I exactly subscribe this event in the frmMain.cs ?

Thanks.

3 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sam Hobbs15y ago
I don't see anything in the code you posted here that is "making it as a public member and using it in the calling form". What I do see is an event handler that uses "object sender, EventArgs args" when it does not need to. I think there are other problems with the code you posted in the original question here. So I truly believe that there is more to this question than "a way to pass back additional parameters to the handler".
sasikumar15y ago
Hi Sam,

Thanks for the response. I just wanted to know if there is a way to pass back additional parameters to the handler in the way specified in my earlier post.

Tried different options but couldn't find any. Finally, I had to stick with the original option of making it as a public member and using it in the calling form. That worked. Thanks.
Sam Hobbs15y ago
Since the parameter (the DataSet) is in the UserControl, you do not need to pass it as a parameter for the handler. You can simply make it a public member of the UserControl and then the form can use that to get it.

So your delegate can be declared as:

public delegate void ClickedEvent();
public ClickedEvent Clicked = null;

Then call it from the UserControl click event as:

if (Clicked != null)
        Clicked();

Note that you should check to see if it has been provided a value, so that is why we check for null. Then in your form:

f.Clicked = controlClicked;

And:

void controlClicked()
{

}