Regex to test if an input string contains a certain number of characters

Posted by Dan on Stack Overflow See other posts from Stack Overflow or by Dan
Published on 2010-04-07T18:41:36Z Indexed on 2010/04/07 18:53 UTC
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regex

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ASP.NET

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validation

So, I basically would like to test to see if a string contains a range of alphanumeric characters. It's to be used as a client-side validation and I don't want to prevent users from entering whatever they want. Best to give examples of what should/should not pass validation:

So to be specific, the expression I'm looking for is to test to make sure string contains anywhere from 3 to 10 alphanumeric characters. I'd like to plug into an ASP.NET client side validator.

NOTE: quotes not part of input (but could be!)

" f o o " should pass since there are 3 chars
"f_0_0" should pass
" fo " should not
"F......o......o......b.....a......r" should pass

thx

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