TalkPHP - preg_match problem

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preg_match problem

When I run this expression in preg_match is returns

Quote:

Warning

Quote:

: preg_match() [function.preg-match]: Unknown modifier ']' in /home/img911/public_html/url/shorten.php on line 16

The expression is

Code:

/^(ftp|http|https):\/\/([_a-z\d\-]+(\.[_a-z\d\-]+)+)(([_a-z\d\-\\\.\/]+[_a-z\d\-\\\/])+)*/

The problem lies in the final character class definition [_a-z\d\-\\\/], the escaping back slashes cause it. They're interpreted (by the PHP parser) to be \\/ which the regex parser decides is a single backslash followed by a forward slash, the pattern delimiter. To match a backslash, you'll need four consecutive backslashes (plus 1 escaping the forward slash!): [_a-z\d\-\\\\\/]

It might also make life easier if you use a different delimiter for the pattern, which would save you having to escape all of those forward slashes: ~test://~ vs /test:\/\//