Calling Child Controls

[grimace]

Hi,
I have a problem referencing the controls in a child class and as I am fairly new to c# I am not sure whether it is actually possible to do what I want to do..phew!! Basically I have a standard dialog that has apply/ok/cancel buttons. It also loads the data from the db depending on what textboxes appear on the form. However I would like to load these textboxes via child classes so that I can have 'StandardDialog' do all the work and have a bunch of custom dialogs that just have textboxes on them. Everything seems ok except that when i search through the controls it only finds the ones on the parent form. Can i reference the ones on the child class? Here is the code.

class StandardDialog : System.Windows.Forms.Form 
{ 
   public StandardDialog() 
   { 
     InitializeComponent(); 
     LoadData() 
   } 

   private void InitializeComponent() 
   { 
     // Ok,Cancel & Apply buttons here 
   } 

   protected void LoadData() 
   { 
     foreach (Control c in Controls) 
     { 
        //Load data from db 
     } 
   } 
} 


class SiteDialog : StandardDialog 
{ 
   public SiteDialog(): base() 
   { 
      InitializeComponent(); 
   } 

   private void InitializeComponent() 
   { 
     // Textboxes loaded here 
   } 
}

Hope someone can help!!

thanks, Martin

 

[gorgor]

You have to pass the control objects from the child to the parent first.

In the child, create a function:

public ArrayList GiveParentControls()
{
    ArrayList list = new ArrayList();
    list.Add(textbox1);  //an instantiated textbox
    list.Add(textbox2);  //an instantiated textbox
    return list;         //return the arraylist of objects
}

And then in the parent, call the function:

ArrayList childControls = GiveParentControls();

You can now access all the controls contained in the ArrayList:

//Get text from first child text box:
//Don't forget to cast the object to a textbox type!
if((TextBox)childControls[0]) != null)
{
    //Do something to the textbox here...
    string myText = ((TextBox)childControls[0]).Text;
}

Now that you have access to the child's textboxes in the parent, you can do anything you want to the textboxes just as if they are actually in the parent.

 

[grimace]

thanks for your reply..i tried it but the parent class didn't recognise the function. With a little help i managed to sort it. Basically the problem was that I was calling the LoadData method in the constructor of the parent class.This was getting called before the child class had been initialised (hence no controls).

To solve i overrided the OnLoad method in the parent class and put the LoadData method call in there.

Thanks again for your help.