Alter Rendered Page in Webbrowser Control

is there a way to alter the rendered HTML page in webbrowser control? What i need is to alter the rendered HTML Page in my webbrowser control to highlight selected text.

What i did is use a webclient and use the webclient.Downloadstring() to get the source code of the page, Highlight specific text then write it again in webbrowser. problm is, images along with that page does not appear since they are rendered as relative path开发者_运维百科.

Is there a way to solve this problem? Is there a way to detect images in a webbrowser control?

Not sure why you need to change the HTML to lighlight text, why not use IHighlightRenderingServices?

To specify a base url when loading HTML string you need to use the document's IPersistMoniker interface and specify a url in your IMoniker implementation.

I suggest you do it a different way, download and replace the text using the webbrowser control, this way your links will work. All you do is replace whatever is in the Search TextBox with the following, say the search term is "hello", then you replace all occurances of hello with the following:

<font color="yellow">hello</font> 

Of course, this HTML can be replaced with the SPAN tag (which is an inline version of the DIV tag, so your lines wont break using SPAN, but will using DIV). But in either case, both these tags have a style attribute, where you can use CSS to change its color or a zillion other properties that are CSS compatible, like follows:

<SPAN style="background-color: yellow;">hello</SPAN>

Of course, there are a zillion other ways to change color using HTML, feel free to search the web for more if you want.

Now, you can use the .Replace() function in dotnet to do this (replace the searched text), it's very easy. So, you can Get the Whole document as a string using .DocumentText, and once all occurances are replaced (using .Replace()), you can set it back to .DocumentText (so, you're using .DocumentText to get the original string, and setting .DocumentText with the replaced string). Of course, you probably don't want to do this to items inside the actual HTML, so you can just loop through all the elements on the page by doing a For Each loop over all elements like below:

For Each someElement as HTMLElement in WebBrowser1.Document.All 

And each element will have a .InnerText/.InnerHTML and .OuterText/.OuterHTML that you can Get (read from) and Set (overwrite with replaced text).

Of course, for your needs, you'd probably just want to be replacing and overwriting the .InnerText and/or the .OuterText.

If you need more help, let me know. In either case, i'd like to know how it worked out for you anyway, or if there is anything more any of us can do to add value to your problem. Cheers.