Question

I need a Javascript and .NET regex that checks a string and lets me know if the string only containers one character other than a space.

I want to prevent users from entering something like “wwwwwwwwww wwwwwwwwwww wwwwwwwwwww” but allow them to enter things like “cccccccc ddddddddd”.

I’m so bad at regex, so I’m sorry for not coming with code.

Answer 1

 string [] inputs = {" sdfasf asdf ", " wwwwww wwwwwww ", " aaaaa bbbb ccccccc"};
 foreach (string input in inputs)
 {
    var match = Regex.Match (input, @"^\s*(\w)(?:\1|\s)*$");
    Console.WriteLine (input + "\t" + match.Success);
 }

The regex doesn’t use any special characters and I believe it will work in javascript as well. In C#, it prints:

sdfasf asdf    False
wwwwww wwwwwww         True
aaaaa bbbb ccccccc     False