Problem to keep Alphanumeric

Question

Hi,
I want to detect the given input string is alphanumeric, with only - and _ inside. How to complete the following?

var matches = Regex.Matches(text, @"^[a-zA-Z0-9-_]+$");

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Many Thanks & Best Regards, Hua Min

Answer 1

try

var matches = Regex.Matches(value, @"^[A-Za-z_-][A-Za-z0-9_-]*$");

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Mark Answered, if it solves your question and Vote if you found it helpful.
Rohit Arora

Answer 2

Thanks.
I mean how I can finish the above part, to show/detect in case that given text is falling out of this condition.

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Many Thanks & Best Regards, Hua Min

Answer 3

try if following works for you

private bool isValid(String value)
        {
            var matches = Regex.Matches(value, @"^[A-Za-z_-][A-Za-z0-9_-]*$");
            return (matches.Count > 0);
        }

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Mark Answered, if it solves your question and Vote if you found it helpful.
Rohit Arora

Answer 4

Try this too:

   bool is_valid = Regex.IsMatch( text, @"^[a-zA-Z0-9\-_]+$" );