using System;
using System.Text.RegularExpressions;

public class Test
{
	public static void Main()
	{
		var str = "ID: JK546|Guitar: 0|Piano: 1|Violin: 0|Expiry: Aug14,2021";
		string pattern = @"(ID: \w+\|)(\w+: \d+\|)+(Expiry: \w+,\d+)";
		Match m = Regex.Match(str, pattern);
		
		foreach(Capture c in  m.Groups[2].Captures) {
		    Console.WriteLine(m.Groups[1].Value + c.Value + m.Groups[3].Value);
		}
	}
}