Project Description
There is a bad design issue in the way UpdatePanels postback asynchronously select elements, making them very slow when the page contains large ListBox or DropDownList controls.
This adapter fixes the problem.


This adapter is written in .Net 3.5 C#.
You need to add a Browser file to your ASP.Net project containing something like this:

<browsers>
<browser refID="Default">
<controlAdapters>
<adapter controlType ="System.Web.UI.WebControls.ListBox" adapterType="Siderite.Web.Adapters.ListControlUpdatePanelFixAdapter" />
<adapter controlType ="System.Web.UI.WebControls.DropDownList" adapterType="Siderite.Web.Adapters.ListControlUpdatePanelFixAdapter" />
</controlAdapters>
</browser>
</browsers>

More information here: http://siderite.blogspot.com/2008/06/very-slow-updatepanel-refresh-when.html

Quick and dirty steps:

Step 1: download the project
Optional step (but recomended): open the Siderite.Ajax project in Visual Studio and compile it and check that it is Debug or release mode, etc.
Step 2: reference the Siderite.Ajax.dll library from the bin folder in your ASP.Net project
Step 3: create a new Browser File in Visual Studio in your ASP.Net project (Add New Item -> Browser File)
Step 4: replace its default content with the XML content above