DomainUpDown Example

How can you present a limited selection of options to your user, while taking up minimal screen space? In Windows Forms, you can provide a DomainUpDown control, which allows users to select one of several items.

This C# tutorial provides an example for the DomainUpDown control in Windows Forms.

Example

First, to add a DomainUpDown control, drag it from the Toolbox to the Window you are designing. A good place to initialize the DomainUpDown control is in the Load event of the enclosing form; double-click on the enclosing form to create this event. This example code shows how you can add several items to the DomainUpDown control. The current item can be determined or set with the Text property.

Program that uses DomainUpDown control [C#]

using System;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
	public Form1()
	{
	    InitializeComponent();
	}

	private void Form1_Load(object sender, EventArgs e)
	{
	    // Items.
	    DomainUpDown.DomainUpDownItemCollection items = this.domainUpDown1.Items;
	    items.Add("Dot");
	    items.Add("Net");
	    items.Add("Perls");

	    // Set Text.
	    this.domainUpDown1.Text = "Dot";
	}

	private void domainUpDown1_SelectedItemChanged(object sender, EventArgs e)
	{
	    // Run code every time the item is changed.
	    this.Text = domainUpDown1.Text;
	}
    }
}

SelectedItemChanged event handler. One of the most useful event handlers on the DomainUpDown control is the SelectItemChanged event handler. Every time the selected item is changed by the user, this code is executed. In the above example program, we set the Text property of the Form to the current item in the DomainUpDown.

Summary

The DomainUpDown control provides an alternative to radio buttons or other pull-down lists. It is a very simple user interface control but can be useful in a variety of program contexts, including preferences dialogs (Options).