# Getting Started with WinForms DomainUpDown

This article shows how you can start using **RadDomainUpDown**.

## Adding Telerik Assemblies Using NuGet

To use `RadDomainUpDown` when working with NuGet packages, install the `Telerik.UI.for.WinForms.AllControls` package. The [package target framework version may vary](https://www.telerik.com/products/winforms/documentation/visual-studio-integration/available-nugets).

Read more about NuGet installation in the [Install using NuGet Packages](https://www.telerik.com/products/winforms/documentation/installation-and-upgrades/install-using-nuget) article.

> tip With the 2025 Q1 release, the Telerik UI for WinForms has a new licensing mechanism. You can learn more about it [here](https://www.telerik.com/products/winforms/documentation/licensing/license-key).

## Adding Assembly References Manually

When dragging and dropping a control from the Visual Studio (VS) Toolbox onto the Form Designer, VS automatically adds the necessary assemblies. However, if you're adding the control programmatically, you'll need to manually reference the following assemblies:

* **Telerik.Licensing.Runtime**
* **Telerik.WinControls**
* **Telerik.WinControls.UI**
* **TelerikCommon**

The Telerik UI for WinForms assemblies can be install by using one of the available [installation approaches](https://www.telerik.com/products/winforms/documentation/installation-and-upgrades/installing-on-your-computer).

## Defining the RadDomainUpDown

The following tutorial demonstrates how to add items and images to a **RadDomainUpDown** and how to retrieve the selected text and image.

> caption Figure 1: Select a country from RadDomainUpDown

![WinForms RadDomainUpDown Select a Country From RadDomainUpDown](https://www.telerik.com/products/winforms/documentation/assets/24a4b9d49b4ad19b0357b550da1ae3e1/editors-domainupdown-getting-started001.gif)

1. Add a **RadDomainUpDown** and a **RadStatusStrip** to a form.

2. Add a few flag images to the project as resources.

3. Using the down arrow of the **RadStatusStrip**, add a **RadLabelElement** and a  **RadButtonElement**. Set the **DisplayStyle** of the **RadButtonElement** to *Image*.

   > caption Figure 2: RadStatusStrip Item Elements

   ![WinForms RadDomainUpDown RadStatusStrip Item Elements](https://www.telerik.com/products/winforms/documentation/assets/7cd1b16747dc6d74603d5566f4ad5970/editors-domainupdown-getting-started002.png)

4. Select **RadDomainUpDown** and find the **Items** property in the *Properties* Window of Visual Studio. Click the  ellipsis button to open the **RadListDataItem Collection Editor**. Click the `Add` button three times to create three list items. Set the text of the first, second and third item to *Bulgaria*, *Canada* and *Germany* respectively. Set the resource images to the **Image** property of the items.

   ![WinForms RadDomainUpDown Design Time](https://www.telerik.com/products/winforms/documentation/assets/1a7c3e2cfa8cd0abd66fdb0b3ad3f744/editors-domainupdown-getting-started003.png)

5. Click **OK** to close the **RadListDataItem Collection Editor**.

6. Set the **ReadOnly** property to *true* for **RadDomainUpDown**.

7. In the *Properties* Window select the **Events** button.

8. Locate and double-click the **SelectedIndexChanged** event to create an event handler.

9. Paste the following code to the **SelectedIndexChanged** event handler. The code retrieves the selected item and assigns the text and image for the selected item to the status bar label and image elements.

#### Handling the SelectedIndexChanged event

```C#
    
        private void radDomainUpDown1_SelectedIndexChanged(object sender, Telerik.WinControls.UI.Data.PositionChangedEventArgs e)
        {
            if (this.radDomainUpDown1.SelectedIndex > -1)
            {
                this.radLabelElement1.Text = this.radDomainUpDown1.SelectedItem.Text;
                this.radButtonElement1.Image = this.radDomainUpDown1.SelectedItem.Image;
            }
        }

```

```VB.NET

Private Sub radDomainUpDown1_SelectedIndexChanged(ByVal sender As Object, ByVal e As Telerik.WinControls.UI.Data.PositionChangedEventArgs)
    If Me.radDomainUpDown1.SelectedIndex > -1 Then
        Me.radLabelElement1.Text = Me.radDomainUpDown1.SelectedItem.Text
        Me.radButtonElement1.Image = Me.radDomainUpDown1.SelectedItem.Image
    End If
End Sub


```

This is it! Now the change in the selection of the **RadDomainUpDown** instance will be reflected on **RadStatusStrip**.

## See Also

* [Structure](https://www.telerik.com/products/winforms/documentation/controls/editors/domainupdown/structure)
* [Design Time](https://www.telerik.com/products/winforms/documentation/controls/editors/domainupdown/design-time)

## Telerik UI for WinForms Learning Resources

* [Telerik UI for WinForms DomainUpDown Component](https://www.telerik.com/products/winforms/domainupdown.aspx)
* [Getting Started with Telerik UI for WinForms Components](https://docs.telerik.com/devtools/winforms/getting-started/first-steps)
* [Telerik UI for WinForms Setup](https://docs.telerik.com/devtools/winforms/installation-and-upgrades/installing-on-your-computer)
* [Telerik UI for WinForms Converter](https://www.telerik.com/products/winforms/documentation/ai-coding-assistant/converter/converter)
* [Telerik UI for WinForms Visual Studio Templates](https://docs.telerik.com/devtools/winforms/visual-studio-integration/visual-studio-templates)
* [Deploy Telerik UI for WinForms Applications](https://docs.telerik.com/devtools/winforms/deployment-and-distribution/application-deployment)
* [Telerik UI for WinForms Virtual Classroom(Training Courses for Registered Users)](https://learn.telerik.com/learn/course/external/view/elearning/17/telerik-ui-for-winforms)
* [Telerik UI for WinForms License Agreement)](https://www.telerik.com/purchase/license-agreement/winforms-dlw-s)