struggling to nail this

[Destramic]

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

 

 

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

[requinix]

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?

[Destramic]

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

[requinix]

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.

[Destramic]

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

 

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

[requinix]

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_]

[Destramic]

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