Assume I have a WebBrowser control called webBrowser1, and I would like to use it to display an image, which changes from time to time. I thought that I could show the most up-to-date image by calling the following line:
webBrowser1.DocumentText = "<img src='foo' width='100%' height='100%'>";
But that didn't work, and looked like WebBrowser kept a cached image.

I tried Refresh() and Refresh(WebBrowserRefreshOption.Complete), and none of those worked either.

I can make it work by set url to foo and then call Refresh(). But that won't work for every situation, for example when I have multiple images on the page.

Figured out. One solution is to do the following:

import this:
[DllImport("wininet.dll")]
private static extern long DeleteUrlCacheEntry(string lpszUrlName);

and call it
DeleteURLCacheEntry(image_url);