Question

I need some help with regular expressions please. (In .Net 4 and C#)

I need to highlighting a block of text. The text is formated html so I am trying to use a regular expression to find the block when I just know the words in it. Then I want to put span tags around it:

For example if I have :

Now x is y the time z for all <bold>quick</bold> brown x foxes to jump over the lazy dogs back"

And I want to highlight “all quick brown foxes”

I want my result string to be:

Now x is y the time z for all <span class="MyHighLight"><bold>quick</bold> brown x foxes</span> to jump over the lazy dogs back"

The tricky part is I need to keep the original text, just put spans tags around it.

I thought I would start with replacing the spaces in the string I want to find with ?* to convert it to a regular expression.
all?*quick?*brown?*foxes

Thanks!

Answer 1

static string Yellow(this string body, string match)
{
    string result = body;
    foreach (Match m in Regex.Matches(body, match.Replace(" ", "(\\s*|(<[^>]+>)*)+")))                
        result = result.Replace(m.Value, 
            string.Concat("<span class=yellow>", m.Value, "</span>"));
    return result;
}

string s = "Now x is y the time z for all <bold>quick</bold> brown foxes to jump over the lazy dogs back";
string m = "all quick brown foxes";
Console.WriteLine(s.Yellow(m));

The result in console is:
Now x is y the time z for <span class=yellow>all <bold>quick</bold> brown foxes</span> to jump over the lazy dogs back