How to validate a string is in YYYY-MM-DD form (C#) <p>Most of the ways I have seen on SO have involved validating a C# date object which is not what I want to do. For what I'm working on, the user will enter a string in a format for example, 1999-02-23. I would like to validate that the string they enter follows the format of YYYY-MM-DD. The solutions I have come up with seem overly complex. </p>