Use
Regex.Replace[
^]
Try this:
using System;
using System.Text.RegularExpressions;
public class Program
{
public static void Main()
{
string input = "<a href='http://oldurl.com'>somewhere</a>";
string pattern = @"(?<=href=[']).+(?=')";
string output = Regex.Replace(input, pattern,"http://newurl.com");
Console.WriteLine(input);
Console.WriteLine(output);
}
}
It will output:
<a href='http://oldurl.com'>somewhere</a>
<a href='http://newurl.com'>somewhere</a>
Learn more about
Regex[
^]