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Regular expression question.

AlfaNoMore asked
Medium Priority
Last Modified: 2010-04-16
Hello all,

I have the following scenario:

Retrieve data from third party via a WebClient object, and load retrieved content into a StringBuilder object.

From there, I want to replace all matches with my own version:

Given the following string "<a href="http://www.xxx.com/cgi?jvsdhjarewh"v ghjgh="">link</a><a href="http://www.xxx.com/cgi?jvsdhjarewh">link</a><a href="http://www.xxx.com/cgi?hjhkhkj">link</a>"

I want to look for the following pattern "<a href="(http://www.xxx.com/\S*?)""

And replace all matches with "<a href="http://www.x.asp?page=$1""

In practice, this works, and returns "<a href="http://www.x.asp?page=http://www.xxx.com/cgi?jvsdhjarewh"v ghjgh="">link</a><a href="http://www.x.asp?page=http://www.xxx.com/cgi?jvsdhjarewh">link</a><a href="http://www.x.asp?page=http://www.xxx.com/cgi?hjhkhkj">link</a>"

However, I must also have the matched pattern ($1) replaced as a URLEncoded string, otherwise the above result will work properly.

I don't know the MatchEvaluator, but wondered if this might be the place to add my own function for this purpose? Or is there a nice little Regexp function that I can enclose my $1 match with?

Thanks for your help.
Watch Question

static void Main(string[] args)
            string s = "<a href=\"http://www.xxx.com/cgi?jvsdhjarewh\"v ghjgh=\"\">link</a><a href=\"http://www.xxx.com/cgi?jvsdhjarewh\">link</a><a href=\"http://www.xxx.com/cgi?hjhkhkj\">link</a>";
            MatchEvaluator me = new MatchEvaluator(ReplaceFunc);
            string result = Regex.Replace(s, "(?<=href=\")(?<link>http://www.xxx.com/[^\"]*)", me);
        static string ReplaceFunc(Match m)
            return "http://www.x.asp?page=" + HttpUtility.UrlEncode(m.Groups["link"].Value);

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Thanks joechina, simple as that eh? :-)
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