Visual Inheritanc Problem in .net

[fahimrauf]

Hy Friends,

Using visual inheritance feature of .net, I've inherited a Form (Form2) from an existing form (Form1) of the same assembly or project. It's perfectly inherited and when I run the application it's executing fine. But when I open the inherited form (Form2) in designer, It throws an exception in form_load event of Parent Form (Form1) as code block in form_load event requires some data which will be available only when application runs. Due to this problem, I can not make changes in Inherited Form (Form2) using designer.

Now, my question is that, why It's going to call Form_Load event of Parent Form (Form1) while opening Inherited Form (Form2) in the designer. Is there any solution to that problem.

Please help.

Thanks.

[TRScheel]

Hy Friends,

Using visual inheritance feature of .net, I've inherited a Form (Form2) from an existing form (Form1) of the same assembly or project. It's perfectly inherited and when I run the application it's executing fine. But when I open the inherited form (Form2) in designer, It throws an exception in form_load event of Parent Form (Form1) as code block in form_load event requires some data which will be available only when application runs. Due to this problem, I can not make changes in Inherited Form (Form2) using designer.

Now, my question is that, why It's going to call Form_Load event of Parent Form (Form1) while opening Inherited Form (Form2) in the designer. Is there any solution to that problem.

Please help.

Thanks.

Could you show code?

My guess is, though, that something like this is what you will find for form2's code:

public class Form2 : Form1
{
     public Form2() : base()
     {
     }
}
 

Though, i dont see why that wouldnt allow you to see Form2 in designer. I have never tried this though...

[fahimrauf]

Could you show code?

here is the code:

Form1 Code:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();

}

private void Form1_Load(object sender, EventArgs e)
{
MessageBox.Show("Parent Form Load Event");
}
}

Form 2 Code:
public partial class Form2 : Form1
{
public Form2()
{
InitializeComponent();
}
}


Now form_load event of Form1 is triggered when I open Form2 in designer and shows message box. But I don't want this behavior and I don't want form_load event to be triggered while opening designer.

[RoninZA]

Hi All,

The problem is that, because you are inheriting Form2 from Form1, when you open Form2 in the designer, the Form_Load event of Form1 will fire (and I assume events like Form_Activate, etc). I don't know if this is intentional or a bug, but I know there must be a couple of ways to get around it, but I think the easiest way would be to put error handling around the offending code (which you should actually already have done).

Hope this helps!

[TRScheel]

You have to remove Form_Load from the Load event handler of the Form1 instance created under Form2.