I want to check whether a string is a file name (name DOT ext) or not.
Name of file cannot contain / ? * : ; { } \
Could you please suggest me the regex expression to use in preg_match()?
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1357answers:
3
+2
A:
Here you go:
"[^/?*:;{}\\]+\\.[^/?*:;{}\\]+"
"One or more characters that aren't any of these ones, then a dot, then some more characters that aren't these ones."
(As long as you're sure that the dot is really required - if not, it's simply: "[^/?*:;{}\\]+"
RichieHindle
2009-06-23 11:59:44
@Richie, do you really need the second backslash just before the dot separator? shouldn't it be ...}\\]+\.[^/?....
Rob Wells
2009-06-23 12:15:10
@Rob Wells: It is necessary since PHP strings use the backslash as an escape character as well. "\\" in a PHP string is translated to "\" in the regex. That "\." is translated to "\." is a coincidence resulting from the fact that "\." has no meaning to PHP and is therefore left unchanged. Nontheless it is sloppy not to escape the backslash.
Tomalak
2009-06-23 12:18:02
error coming. might be my mistake, please seeI entered $page_regex = "[[^/?*:;{}\\]+\\.[^/?*:;{}\\]+"; $len = $this->REQ_URI_PATH_E_LEN; //length of $this->REQ_URI_PATH_E_LEN given below $page = $this->REQ_URI_PATH_E[$len - 1]; //holds path elements like 0=>posts, 1=>hello, 2=>newp.php for localhost/posts/hello/newp.php?id=3 if(preg_match($page_regex,$page)) echo "page"; else echo "Folder";error is "Warning: preg_match() [function.preg-match]: No ending matching delimiter ']' found in *line*"I might be wrong with the syntax, please correct me.
OrangeRind
2009-06-23 12:37:56
You have two opening brackets right at the start of the string: "[[
RichieHindle
2009-06-23 12:44:42
sorry probably typobut "[^/?*:;{}\\]+\\.[^/?*:;{}\\]+" is what i entered and it gave the error. Copied it now straight from your answer to this comment and my code as well:(
OrangeRind
2009-06-23 13:17:28
Perhaps you need to escape the forward slashes: [^\/?*:;{}\\]+\\.[^\/?*:;{}\\]+
RichieHindle
2009-06-23 13:31:44
no luck. but $page_regex is showing [^\/?*:;{}\]+\.[^\/?*:;{}\]+ on echo.gawd. this regex mumbo jumbo is getting on mah nerves
OrangeRind
2009-06-23 13:40:57
even [^/?*:;{}\\]+\\.[^/?*:;{}\\] doen't work.whats the + at the end for (in your answer)?
OrangeRind
2009-06-23 13:50:47
+ means "one or more". I suggest you write a self-contained failing example and post that, and the errors you're getting, in a new question.
RichieHindle
2009-06-23 14:31:27
+1
A:
The regex would be something like (for a three letter extension):
^[^/?*:;{}\\]+\.[^/?*:;{}\\]{3}$
PHP needs backslashes escaped, and preg_match() needs forward slashes escaped, so:
$pattern = "/^[^\\/?*:;{}\\\\]+\\.[^\\/?*:;{}\\\\]{3}$/";
To match filenames like "hosts" or ".htaccess", use this slightly modified expression:
^[^/?*:;{}\\]*\.?[^/?*:;{}\\]+$
Tomalak
2009-06-23 12:02:07
You can of course you something other than "/" to delimit the regex in preg_match(), this removes the need to escape forward slashes specifically, but adds the need to escape the new delimiter character (if you want to use it in the regex).
Tomalak
2009-06-23 12:13:00
+1
A:
$a = preg_match('=^[^/?*;:{}\\\\]+\.[^/?*;:{}\\\\]+$=', 'file.abc');
^ ... $ - begin and end of the string
[^ ... ] - matches NOT the listed chars.
hegemon
2009-06-23 12:05:23