hello
i use datalist and inside i have dropdownlist onselectindexchanged event inside the itemtemplate, i am getting selected value from drowdown and sending into another page.
first selection items works fine. So, once i sent the selected value to another page and coming back (using browser back button) to dropdown page. everything shows as it is as caching does this. 
Now, if i choose another value from dropdown list, it is calling onselectindexchanged event but it is getting the first chosen value always and sending to another page.. 
So, i came to know that unless page referesh , it is not. so i put this code on page load event on datalist-dropdownlist page. which makes no caching
page load event
Response.Cache.SetCacheability(HttpCacheability.NoCache); Response.Cache.SetExpires(DateTime.Now.AddSeconds(-1)); Response.Cache.SetNoStore(); Response.AppendHeader("Pragma", "no-cache"); ...

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