Regular expression - starting and ending with a letter, accepting only letters, numbers and _

Posted by jreid9001 on Stack Overflow See other posts from Stack Overflow or by jreid9001
Published on 2010-05-12T17:52:55Z Indexed on 2010/05/12 17:54 UTC
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regex

I'm trying to write a regular expression which specifies that text should start with a letter, every character should be a letter, number or underscore, there should not be 2 underscores in a row and it should end with a letter or number. At the moment, the only thing I have is ^[a-zA-Z]\w[a-zA-Z1-9_] but this doesn't seem to work properly since it only ever matches 3 characters, and allows repeated underscores. I also don't know how to specify requirements for the last character.

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Regular expression - starting and ending with a letter, accepting only letters, numbers and _ - Developer IT

Regular expression - starting and ending with a letter, accepting only letters, numbers and _

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