How do I get the name of captured groups in a C# Regex?

Question

Is there a way to get the name of a captured group in C#?

string line = "No.123456789  04/09/2009  999"; Regex regex = new Regex(@"(?<number>[\d]{9})  (?<date>[\d]{2}/[\d]{2}/[\d]{4})  (?<code>.*)");  GroupCollection groups = regex.Match(line).Groups;  foreach (Group group in groups) {     Console.WriteLine("Group: {0}, Value: {1}", ???, group.Value); } 

I want to get this result:

 Group: [I don´t know what should go here], Value: 123456789  04/09/2009  999 Group: number, Value: 123456789 Group: date,   Value: 04/09/2009 Group: code,   Value: 999 

Answer 1

Use GetGroupNames to get the list of groups in an expression and then iterate over those, using the names as keys into the groups collection.

For example,

GroupCollection groups = regex.Match(line).Groups;  foreach (string groupName in regex.GetGroupNames()) {     Console.WriteLine(        "Group: {0}, Value: {1}",        groupName,        groups[groupName].Value); }