用正则表达式替换和删除？

Question

if (Result.Contains("http://"))
{
  string pattern = @"(http://)";
  theend = Result.Substring(Result.IndexOf("http://"));
  Regex rgx = new Regex(pattern);
  string replacement = "<a href="+theend+">"+theend+"</a> ";
  Result = rgx.Replace(Result, replacement);
}

The result is normal link (a href) and after that there is a string http://. How do I get only a link?

Answer 1

Not clear exactly what are you trying to do. how does the input Result looks like. if Result only contains the URL then just change:

Result = rgx.Replace(Result, replacement);

to

Result = replacement;

Update:

Anyway, You can use this function:

private string ConvertUrlsToLinks(string msg) {
        string regex = @"((www\.|(http|https|ftp|news|file)+\:\/\/)[&#95;.a-z0-9-]+\.[a-z0-9\/&#95;:@=.+?,##%&~-]*[^.|\'|\# |!|\(|?|,| |>|<|;|\)])";
        Regex r = new Regex(regex, RegexOptions.IgnoreCase);
        return r.Replace(msg, "<a href=\"$1\">$1</a>").Replace("href=\"www", "href=\"http://www");
    }