[RESOLVED] reg ex help

[kbc1]

Hi all

Newbie to regex so would really appreciate some help.

I am retrieving a large string from the database and before outputting anything to the browser, I am looking to see if a certain substring or pattern exists in the large string itself so I can store it to a variable and later manipulate it.

The string pattern I am looking for is:

<%RG

Now, this string would normally be something like:

<%RG_1_4> or <%RG_2_3> where the rest of the characters before the last greater than symbol (>) are different each time.

I need to be able to detect the string <%RG and then store it, and all characters up to the last > symbol into a variable.

so basically look for <%RG?_?> where question marks are a range of numbers numbers and store it to a variable.

Is Regex the way to achieve this and if so, can someone help and provide code on how to do it?

Many Thanks and I hope I have made sense!

[NogDog]

untested:

preg_match('/<%_RG[^>]*>/', $text, $matches);
$result = (!empty($matches[0])) ? $matches[0] : '';

[nrg_alpha]

$str = '<%_RG_2_16>';
if(preg_match('#<%_RG_\d+_\d+>#', $str, $match)){
    echo $match[0];
}

Nog, I think the one thing about your pattern is that it can match <%RGblah> for instance. Since the OP requires the underscore after the RG as well as digits separated by more underscores, I modified the pattern, just in case there are possibilities of other variations of <%RG that could exist (but admittedly, it may be simply considered splitting hairs on this one.. not sure).

@OP: As it currently stands (without knowing the details of what possible variations / conditions might exist), both versions will suffice, truth be told...Just that one is more strict than the other.

[kbc1]

Thanks for the advice guys, that's really helpful however I forgot to mention that this string pattern might exists more than once so I need to extract and store each occurrence of it.

I implemented your code and it only seems to store the first occurrance of the string pattern found.

Can it be edited so that it searches the entire large string ($str) and stores every occurance of the pattern I am looking for into an array?

Many Thanks once again.

[Weedpacket]

[man]preg_match_all[/man] (cited on the [man]preg_match[/man] page).

[nrg_alpha]

kbc1;10909850 wrote:

Thanks for the advice guys, that's really helpful however I forgot to mention .....

Always remember, 10 out of 10 times, peoples' crystal balls are broken and in the shop. Thus, when posting, first mentally collect all the aspects of the problem at hand prior to posting. Would make the problem solving flow of things that much smoother.

Just a heads up, when using preg_match_all, this will create a multi-dimensional array. You will want to fetch the contents from match[0] instead of simply match.