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Internally Initialize Derived ComboBox Items List?

I have a class that derives from ComboBox. I want to fill the Items list inside its constructor. Problem is, when I add it to another control (using the designer) the initialization gets put in the parent’s InitializeComponent() method. This doubles the items in the list.

How to stop the designer from doing this?

If this is not posible then:

What is the best practice for Initializing an Items list in a child class that derives from ComboBox?

ElectricBliss Monday, July 14, 2008 12:26 AM

Ensure the items are only ever added once:

using System;
using System.Windows.Forms;

public class MyCombo : ComboBox {
protected override void OnHandleCreated(EventArgs e) {
base.OnHandleCreated(e);
if (this.DesignMode && this.Items.Count == 0) {
this.Items.Add("one");
this.Items.Add("two");
this.Items.Add("three");
}
}
}

nobugz Tuesday, July 15, 2008 6:33 PM

If you dont need the items there in Design-Time, then you can make your Combo implement ISupportInitialize and add the items in the EndInit method.

hth,
Lior.

Lior Salem Tuesday, July 15, 2008 7:25 PM

nobugz Tuesday, July 15, 2008 6:33 PM

If you dont need the items there in Design-Time, then you can make your Combo implement ISupportInitialize and add the items in the EndInit method.

hth,
Lior.

Lior Salem Tuesday, July 15, 2008 7:25 PM

You can use google to search for other answers

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