---
uid: web-forms/videos/aspnet-ajax/how-do-i-create-an-aspnet-ajax-extender-from-scratch
title: "[How Do I:] Create an ASP.NET AJAX Extender from Scratch? | Microsoft Docs"
author: rick-anderson
description: "Learn how to create an ASP.NET AJAX extender for a standard ASP.NET server control. We are shown how to add server-side properties and client-side JavaScript..."
ms.author: riande
ms.date: 09/01/2007
ms.assetid: 526b4ec1-4a80-4fae-bf0d-af5cb78f5d02
msc.legacyurl: /web-forms/videos/aspnet-ajax/how-do-i-create-an-aspnet-ajax-extender-from-scratch
msc.type: video
---
[How Do I:] Create an ASP.NET AJAX Extender from Scratch?
====================
by [Chris Pels](https://twitter.com/chrispels)

Learn how to create an ASP.NET AJAX extender for a standard ASP.NET server control. We are shown how to add server-side properties and client-side JavaScript to extend the behavior of the standard TextBox control, though the same approach can be applied to any other server control. For further help in creating an ASP.NET AJAX extender, please refer to the [Creating a New Extender](../../overview/ajax-control-toolkit/getting-started/creating-a-custom-ajax-control-toolkit-control-extender-cs.md) walkthrough.

[▶ Watch video (15 minutes)](https://channel9.msdn.com/Blogs/ASP-NET-Site-Videos/how-do-i-create-an-aspnet-ajax-extender-from-scratch)

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