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Destramic

struggling to nail this

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i'm sorry for having to post a simular thread but i'm really struggling to get my pattern to work after many attempts...i've tried playing around with it but its just not matching multiple patterns :confused:

 

 

this will work great

$uri = "/i:news_id";

if (preg_match_all('/(??!\[\/).)*^\/(i|a|h)?[A-Za-z0-9_]+)$(??!\]))/', $uri, $parameters))
{
    print_r($parameters);
}

but when chaging this part of the code it won't work

$uri = "/i:news_id/:hello";

examples of matching are:

 

/:test

/i:test

/a:test

/b:test

 

 

but i only want a match as long as the pattern isn't wrapped inside brakcets [ ]

 

invalid:

 

[/:test]

 

 

i thought the ^ start and $ end characters would have been all i needed...any advise wouldnt greatful...thank you

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So what has changed since

brilliant thank you very much requinix.

 

i used this pattern which seems to work fine

/(i|s)+:+([A-Za-z0-9_-]\w*)/

 

last time? I thought this was from a URI, but if that's true then where are these brackets coming from?

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well my routing system may contain something like this:

 

/search/xbox[/category/:category]

 

matching:

 

/search/xbox 

/search/xbox/category/consoles

 

so i decided to make my pattern a bit stonger so it match uri vars which are not inside brackets...so yeah my pattern has changed slightly...with the regex in this posts and the others i'm working on i get the problem of matching multiple patterns in the same string...this is my only problem.

 

can you please tell me where i'm going wrong...thank you

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But what about a case like

/search/xbox[/category/:category[/subcategory/:subcategory]]
This becomes a problem of balanced brackets - simply checking for [] on either side isn't enough.

 

Two suggestions for how to handle this:

a) Don't allow optional variables and force the user to make additional routes. I've done this and it helps if you can give the user a way to configure routing in a recursive way, like

<route path="/search/xbox">
	route information here...

	<route path="/category/:category">
		additional overriding information here...
	</route>
</route>
The routing system matches as much as it can, gathers all the information along the way, and decides what to do. You could also support

<route path="/search">
	route information...

	<route path="/xbox">
		route information...

		<route path="/category/:category">
			route information...
		</route>
	</route>
</route>
where the route information gathered for just "/search" isn't enough to serve a page and thus results in some 404-type behavior.

 

b) Use regular expressions to turn the route pattern into another regular expression. I've done this one too. With your simple example you could have something like

$route = "/search/xbox[/category/:category]";

// escape any regex metacharacters already present
$regex = preg_quote($route, '#'); // if using # as the pattern delimiters
// note that it will escape any of . \ + * ? [ ^ ] $ ( ) { } = ! < > | : -
// or you can make this much simpler by not escaping characters and trusting the user to write mostly-regex-safe patterns

// transform escaped brackets
$regex = preg_replace('/\\\\\[/', '(?:', $regex);
$regex = preg_replace('/\\\\\]/', ')?', $regex);

// transform variables
$regex = preg_replace('/\\\\:(\w+)/', '(?P<$1>[^/]+)', $regex); // replace [^/]+ with whatever you think matches a variable

var_dump($regex); // "/search/xbox(?:/category/(?P<category>[^/]+))?"
then

if (preg_match('#^' . $regex . '$#', $url, $matches)) {
gives you stuff like

Array
(
    [0] => /search/xbox
)
Array
(
    [0] => /search/xbox/category/consoles
    [category] => consoles
    [1] => consoles
)
The route gets [0] for the full match, and both named (useful) and numeric (useless) captures matching the assorted variables (if present).

 

 

 

Why did I just say all that? Because at 4:30am I'm not seeing a "nice" way of solving your particular problem of dealing with the []s.

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Why did I just say all that? Because at 4:30am I'm not seeing a "nice" way of solving your particular problem of dealing with the []s.

 

for 4:30am you've come up with some good solutions :happy-04:

 

i do like the first option and it does get rid of the bother caused by the brackets and you've openned my mind up to another soltion, thank you...options 2 is what i'm currently doing at the moment.

 

although my regex knowledge is poor could you please explain to me how i can make this pattern match multiple please?

$uri = "/i:news_id/:hello";

if (preg_match_all('/^\/(i|a|h)?[A-Za-z0-9_]+)$/', $uri, $parameters))
{
    print_r($parameters);
}

thank you for your great information

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although my regex knowledge is poor could you please explain to me how i can make this pattern match multiple please?

$uri = "/i:news_id/:hello";

if (preg_match_all('/^\/(i|a|h)?:([A-Za-z0-9_]+)$/', $uri, $parameters))
{
    print_r($parameters);
}

 

It would match fine if you didn't use the ^ and $ anchors that force the regex to test the entire string at once.

 

And by the way, a slightly cleaner version:

#/([ahi]?):(\w+)#
- # delimiters so you don't have to escape the /s (you can use just about anything as a delimiter and / # ! ~ are the most common)

- [ahi] so you don't need | alternation

- [ahi]? inside the capturing group so it always captures something (even if it is just an empty string)

- \w is equivalent to [A-Za-z0-9_]

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wel i feel a lot wiser now...thank you for the breakdown and all your help requinix :happy-04:

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