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scope and object types - not knowing before initializing

I am calling a method from an event in a webcontrol, this event passes the sender object, which I want to use.

I want to take the sender object, in whatever form it is, say a button or linkbutton, and put it into a reference.

As I first set out to write this code: I check the type of the object, and depending on what type it is, I cast that type into my var for holding, only problem is, oh yeah it's out of scope when I leave my statement block, and I don't know the type beforehand to define it directly in the method.

How do I define a reference to the sender object, cast to the correct type, that is accessible from within my event method (in the case below "submitForm") without knowing the type of the sender beforehand?


protected void submitForm(object sender, System.EventArgs e)
{
      if ( sender.GetType().Name.ToString() == "Button")
      {
            Button submitter = (Button)sender;
      }
      else if ( sender.GetType().Name.ToString() == "LinkButton")
      {
            LinkButton submitter = (LinkButton)sender;
      }
      // submitter reference not available
}
0
sethUSer420
Asked:
sethUSer420
1 Solution
 
dukkorgCommented:
Something like this should work:

protected void submitForm(object sender, System.EventArgs e)
{
    Button submitter = sender as Button;

    if (submitter != null)
    {
        // Got the submitter... You can do what ever you want with it
    }
    else
    {
        // Couldn't to get the submitter.
    }
}

You could do the same thing for a LinkButton.

I don't think I get what your talking about with it being out of scope. The sender is passed into the method so it would be in scope.
0
 
sethUSer420Author Commented:
what if submitter could be a Button or -something else-

aka

Button submitter - sender as Button;

wouldn't work if submitter is a LinkButton
0
 
TheAvengerCommented:
It depends on what you want to do after the end of this if. If you want to execute something which is part of the control class, you can do it like this:

protected void submitForm(object sender, System.EventArgs e)
{
     Control submitter = (Control)sender;

     // Do whatever which is part of the control class....
}

If you want to do things that are specific for buttons or link buttons, you have to write the whole code inside the if statement
0
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sethUSer420Author Commented:
that's weak
0
 
TheAvengerCommented:
What do you mean "weak"?
0
 
sethUSer420Author Commented:
it's weak that I can't make

protected void submitForm(object sender, System.EventArgs e)
{
     if ( sender.GetType().Name.ToString() == "Button")
     {
          Button submitter = (Button)sender;
     }
     else if ( sender.GetType().Name.ToString() == "LinkButton")
     {
          LinkButton submitter = (LinkButton)sender;
     }
     // have reference available here// // can't do it?
}

work
0
 
TheAvengerCommented:
What do you want to do with the submitter at the point:

// have reference available here// // can't do it?

I showed you how you can do it by declaring the submitter as a Control object. It is not possible to have one variable being of two types. However both Button and LinkButton are Controls, so this is their common parent and the only way to use a single variable
0
 
_TAD_Commented:
try something like this...



      private void button1_Click(object sender, System.EventArgs e)
      {
         Control submitter;



         if (sender.GetType().Equals(typeof(Button)))
            submitter = (Button)sender;
         else
            submitter = (TextBox)sender;
         


         Console.WriteLine(submitter.GetType());
      }
0
 
TheAvengerCommented:
No need for this if _TAD_, my solution makes the same with less code...
0
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