title: C# - How can I validate a string to be in the format hh:mm:ss:fff?
body: <p>I was wondering if someone might be able to help me with this. I need to validate a text input from a textbox. I need to make sure it is in a format acceptable by a TimeSpan. The format expect should be hh:mm:ss:fff (i.e hours, minutes, seconds and milliseconds. e.g 15:30:45:040)</p>