when we put a code in drop down list to change the theme, we put the Response.Redirect(Request.Url.ToString()); which causes the page to load again , so the pre init event occurs, then the page load event occurs, then the drop down list event occurs again which causes in my opinion another Response.Redirect(Request.Url.ToString()); and so on the events will repeat, isn't this right?

Did you try it out and did you get in an infinite loop? Nope; which shows this isn't the case.

When you redirect, you request a new page which is in no way associated with the previous one. So, when the new page is requested, the SelectedIndexChanged of the drop down list doesn't occur and the page doesn't post back to the server.

Does this explain things?

Imar

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Imar Spaanjaars
http://Imar.Spaanjaars.Com
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Author of Beginning ASP.NET 4.5 : in C# and VB, Beginning ASP.NET Web Pages with WebMatrix
and Beginning ASP.NET 4 : in C# and VB.
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