The C1InputNumberExtender widget allows you to add preset numbers to a drop-down list box. Use the ShowTrigger property to show the drop-down arrow and use the ComboItems property to populate the drop-down list.

1. Create an ASP.NET Web application.
2. Add a standard TextBox control to the main content of  your page.
3. Click the TextBox smart tag and select Add Extender from the Tasks menu.
4. In the Extender Wizard, select C1InputNumberExtender and click OK. A C1InputNumberExtender control is added to the page and the TargetControlID is set to TextBox1.
5. Select View | Properties Window in the Visual Studio menu.
6. Click the drop-down list at the top of the Properties window and select TextBox1_C1InputNumberExtender.
7. Set the C1InputNumberExtender.NumberType property to Currency.
8. Set the C1InputExtenderBase.ShowTrigger property to True.
9. Click the ellipsis button next to the C1InputExtenderBase.ComboItems property. Add four members.
   

10. Press F5 to run the application. The showTrigger option displays the drop-down arrow. The type sets the values in the drop-down list to currency. The drop-down list specified in the comboItems option contains four preset values.