Using regex to filter strings by length

I am trying to validate a input field with regex with this pattern [A-Z开发者_StackOverflowa-z]{,10} I want it to only find a match if 10 or less chars was sent in the input field, the problem I get is that it will match all words that is less then 10 chars.

Is there a way to say if there is more then 10 chars in the input field come back as false, or is it just better to do a strlen with php?

If you need to validate that it's alphabetic only, don't use strlen(). Instead, put boundaries (^$) on your regex:

/^[A-Za-z]{,10}$/

There is an important syntax mistake being made here by the OP and all the current regex answers: When using the curly brace quantifier with PHP (PCRE), you need to specify the first number. (i.e. The expression: {,10} is NOT a valid quantifier!) Although the comma and second number are optional, the first number in a curly brace quantifier is required. Thus the expression should be specified like so:

if (preg_match('/^[A-Za-z]{0,10}$/', $text))
    // Valid input
else
    // Invalid input

If you just match ^[A-Za-z]{,10}$ it will check that the whole string is 10 or less.

^[A-Za-z]{,10}$

$@#$^&$a36#&$^ will pass your regexp because a is substring of it and a pass [A-Za-z]{,10}

If you are only interested in the length of the string, regex is heavy-handed and you should use strlen instead.