How do I access named capturing groups in a .NET Regex?
You specify the named capture group string by passing it to the indexer of the Groups
property of a resulting Match
object.
Here is a small example:
using System;
using System.Text.RegularExpressions;
class Program
{
static void Main()
{
String sample = "hello-world-";
Regex regex = new Regex("-(?<test>[^-]*)-");
Match match = regex.Match(sample);
if (match.Success)
{
Console.WriteLine(match.Groups["test"].Value);
}
}
}
The following code sample, will match the pattern even in case of space characters in between. i.e. :
<td><a href='/path/to/file'>Name of File</a></td>
as well as:
<td> <a href='/path/to/file' >Name of File</a> </td>
Method returns true or false, depending on whether the input htmlTd string matches the pattern or no. If it matches, the out params contain the link and name respectively.
/// <summary>
/// Assigns proper values to link and name, if the htmlId matches the pattern
/// </summary>
/// <returns>true if success, false otherwise</returns>
public static bool TryGetHrefDetails(string htmlTd, out string link, out string name)
{
link = null;
name = null;
string pattern = "<td>\\s*<a\\s*href\\s*=\\s*(?:\"(?<link>[^\"]*)\"|(?<link>\\S+))\\s*>(?<name>.*)\\s*</a>\\s*</td>";
if (Regex.IsMatch(htmlTd, pattern))
{
Regex r = new Regex(pattern, RegexOptions.IgnoreCase | RegexOptions.Compiled);
link = r.Match(htmlTd).Result("${link}");
name = r.Match(htmlTd).Result("${name}");
return true;
}
else
return false;
}
I have tested this and it works correctly.
Use the group collection of the Match object, indexing it with the capturing group name, e.g.
foreach (Match m in mc){
MessageBox.Show(m.Groups["link"].Value);
}