DataAnnotations validation (Regular Expression) in asp.net mvc 4 - razor view

Question

The DataAnnotations validator not working in asp.net mvc 4 razor view, when using the special characters in the regular expression.

Model:

Answer 1

Try @ sign at start of expression. So you wont need to type escape characters just copy paste the regular expression in "" and put @ sign. Like so:

[RegularExpression(@"([a-zA-Z\d]+[\w\d]*|)[a-zA-Z]+[\w\d.]*", ErrorMessage = "Invalid username")]
public string Username { get; set; }