PHP Regular Expression Failing - php

Question

My current regular expression should be correct, though I wouldn't expect so, it doesn't work properly. It won't return "Got Match"
My currrent code is as follows:
$id = "http://steamcommunity.com/id/TestID";
if (preg_match("^http://steamcommunity\.com/id/.*?\n$", $id)) {
print "Got match!\n";
}

Answer 1

You're missing delimiters on your regex:
if (preg_match("#^http://steamcommunity\.com/id/.*?\n$#", $id)) {
^--here ^--here
Note that I've used # as the delimiter here, since that saves you having to escape all of the internal / charrs, if you'd used the traditional / as the delimiter.

Answer 2

You need a delimiter, like this:
if (preg_match("#^http://steamcommunity\.com/id/.*?$#", $id)) {
^ ^
And what's with the newline at the end? Surely you don't need that.

Answer 3

You're missing delimiters. For example:
"#^http://steamcommunity\.com/id/.*?\n$#"
Also, you're trying to match a newline (\n) that isn't in your string.

Answer 4

You need to add the pattern delimiter:
$id = "http://steamcommunity.com/id/TestID";
if (preg_match("#^http://steamcommunity\.com/id/.*?(\n|$)#", $id)) {
print "Got match!\n";
}

Answer 5

There are a couple of things that are wrong with it. First of all, you need to delimit the start and end of your regex with a character. I used #. You're also matching for a new line at the end of your regex, which you don't have and likely won't ever have in your string.
<?php
$id = "http://steamcommunity.com/id/TestID";
if (preg_match("#^http://steamcommunity\.com/id/.*?$#", $id)) {
print "Got match!\n";
}
?>
http://codepad.viper-7.com/L7XctT

Answer 6

First of all, your regex shouldn't even compile because it's missing delimiters.
if (preg_match("~^http://steamcommunity\.com/id/.*?\n$~", $id)) {
^---- these guys here -----^
Second of all, why do you have a \n if your string doesn't contain a new line?
And finally, why are you using regex at all? Effectively, you are just trying to match a constant string. This should be equivalent to what you are trying to match:
if (strpos($id, 'http://steamcommunity.com/id/') === 0) {

Answer 7

You need to have starting and ending delimiter in your pattern like /pattern/ or #pattern# or with brackets (pattern). Why is that? To have some pattern modifiers after ending delimiter like #pattern#i (ignore case)
preg_match('(^http://steamcommunity\.com/id/.*?\n$)', $id)

Answer 8

As the say your patten is start and end wrong. (Delimiter)
But this will be a better match of a 64-bit Steam ID. (Minimum 17 and Maximum 25 numbers)
if( preg_match("#^http://steamcommunity\.com/id/([0-9]{17,25})#i", $id, $matches) )
{
echo "Got match! - ".$matches;
}
I believe that there is no need for you to require that the string must end with a line break.
Explanation.
http://steamcommunity\.com/id/([0-9]{17,25})
^--- string ---^^-- Regexp --^
[0-9] - Match a number between 0 to 9
{17,25} - Make 17 to 25 matches
() - Returns match
Or use pattern as those (It is the same):
/^http:\/\/steamcommunity\.com\/id\/([0-9]{17,25})/i
(^http://steamcommunity\.com/id/([0-9]{17,25}))i
Regular Expressions PHP Tutorial
Online regular expression testing <- Dont use delimiter.

Answer 9

<?php
# URL that generated this code:
# http://txt2re.com/index-php.php3?s=http://steamcommunity.com/id&-1
$txt='http://steamcommunity.com/id';
$re1='(http:\\/\\/steamcommunity\\.com\\/id)'; # HTTP URL 1
if ($c=preg_match_all ("/".$re1."/is", $txt, $matches))
{
$httpurl1=$matches[1][0];
print "($httpurl1) \n";
}
#-----
# Paste the code into a new php file. Then in Unix:
# $ php x.php
#-----
?>
Resorces:
http://txt2re.com/index.php3?s=http://steamcommunity.com/id&-1