Question

I have array of strings and I have to add hyperlink to every single match of item in array and given string.
Principally something like in Wikipedia.

Something like:

private static string AddHyperlinkToEveryMatchOfEveryItemInArrayAndString(string p, string[] arrayofstrings)

{            }

string p = "The Domesday Book records the manor of Greenwich as held by Bishop Odo of Bayeux; his lands were seized by the crown in 1082. A royal palace, or hunting lodge, has existed here since before 1300, when Edward I is known to have made offerings at the chapel of the Virgin Mary.";

arrayofstrings = {"Domesday book" , "Odo of Bayeux" , "Edward"};

returned string = @"The <a href = "#domesday book">Domesday Book</a> records the manor of Greenwich as held by Bishop <a href = "#odo of bayeux">Odo of Bayeux</a>; his lands were seized by the crown in 1082. A royal palace, or hunting lodge, has existed here since before 1300, when <a href = "#edward">Edward<a/> I is known to have made offerings at the chapel of the Virgin Mary.";

What is the best way of doing that?

Answer 1

You could probably quite easily do it like this:

foreach(string page in arrayofstrings)
{
    p = Regex.Replace(
        p, 
        page, 
        "<a href = \"#" + page.ToLower() + "\">$0</a>", 
        RegexOptions.IgnoreCase
    );
}
return p;

If the capitalization of the anchor can be the same as the matched text, you can even get rid of the for-loop:

return Regex.Replace(
    p,
    String.Join("|", arrayofstrings),
    "<a href = \"#$0\">$0</a>",
    RegexOptions.IgnoreCase
);

Now the pattern becomes Domesday book|Odo of Bayeux|Edward, matches are found regardless of capitalization, and whatever is found is put back both into the link text and into the href attribute.