---
uid: web-forms/videos/aspnet-ajax/how-do-i-build-a-custom-aspnet-ajax-server-control
title: "[How Do I:] Build a Custom ASP.NET AJAX Server Control? | Microsoft Docs"
author: rick-anderson
description: "Learn how to create a custom Web server control with ASP.NET AJAX functionality using the AJAX extensions in the Microsoft AJAX Library. This video walks you..."
ms.author: aspnetcontent
manager: wpickett
ms.date: 07/25/2007
ms.topic: article
ms.assetid: 1165e0b4-2240-4dc2-aa94-ef6664c71a8c
ms.technology: dotnet-webforms
ms.prod: .net-framework
msc.legacyurl: /web-forms/videos/aspnet-ajax/how-do-i-build-a-custom-aspnet-ajax-server-control
msc.type: video
---
[How Do I:] Build a Custom ASP.NET AJAX Server Control?
====================
by [Chris Pels](https://twitter.com/chrispels)

Learn how to create a custom Web server control with ASP.NET AJAX functionality using the AJAX extensions in the Microsoft AJAX Library. This video walks you through both the server-side .NET code and the client-side JavaScript code, and provides an explanation of the 'prototype' concept. The custom ASP.NET AJAX control can then be used in an .aspx page like any other server control.

[▶ Watch video (20 minutes)](https://channel9.msdn.com/Blogs/ASP-NET-Site-Videos/how-do-i-build-a-custom-aspnet-ajax-server-control)

>[!div class="step-by-step"]
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