How to refresh just a specific portion of an HTML page?

I have one HTML file containing several <div> elements. I want to refresh just part of the page using either JavaScript or C#. Can someone help?

I am trying to do it this way:

document.location.reload(开发者_开发问答document.getElementById("contentdiv"));

It reloads the whole page. I wish to reload contentdiv. If contentdiv is at the middle of the page then it should load only that part.

Thank you.

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You could move the contents of everything you want reloaded into an external file, and either use the <iframe> tag and only refresh that frame, or you could use JavaScript and refresh the div with Ajax.

Ajax isn't that simple to explain in a short answer, but you can find plenty of information on it here: http://www.w3schools.com/Ajax/ajax_example.asp or if you use a framework like jQuery ajax is much easier.

iFrames can be implemented (on mypage.html, for example) like so: <iframe src='mypagecontent.html'></iframe> and in mypagecontent.html you could use <script type='text/javascript'>window.location.reload();</script> to refresh the frame.

Not sure if this is what you're looking for, but hope it helps somewhat.

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What ASP.NET Framework are you using? If you are using Web Forms, look into UpdatePanel