PHP: preg_split

Question

Hey guys, I need help on regular expression here.

I want PHP to be able to splits a string in sections of arrays such that a substring enclosed by <%me %> will be in its own slot.

So for example,

Hi there how are <%me date(); %> => {"Hi there how are ", "<%me date(); %>} 
Hi there how are you<%me date(); %> => {"Hi there how are you", "<%me date(); %>}
Hi there how are you<%me date(); %>goood => {"Hi there how are you", "<%me date(); %>, "good"
Hi there how are you<%me date(); %> good => {"Hi there how are you", "<%me date(); %>}, " good"}

Note the white space won't hinder the tags from getting parsed in.

Answer 1

On capturing the splitting delimiter in PREG

You can use PREG_SPLIT_DELIM_CAPTURE to split on and capture the delimiter.

Remember to put the delimiter in a capturing group (…) for this to work properly.

Here's an example:

$text = 'abc123xyz456pqr';

$parts = preg_split('/(\d+)/', $text, -1, PREG_SPLIT_DELIM_CAPTURE);

print_r($parts);

This prints (as seen on ideone.com):

Array
(
    [0] => abc
    [1] => 123
    [2] => xyz
    [3] => 456
    [4] => pqr
)

References

• regular-expressions.info/Brackets for Capturing
• preg-split - PREG_SPLIT_DELIM_CAPTURE
  • If set, parenthesized expression in the delimiter pattern will be captured and returned as well.

---

Back to the question

In this case, you can try the delimiter pattern (<%me[^%]+%>). That is:

• <%me, literally
• [^%]+, i.e. anything but %
• %>, literally
• The whole thing captured in group 1

If % can appear in the tag, then you can try something like (<%me.*?%>).

Here's an example:

$text = 'prefix<%me date() %>suffix';

$parts = preg_split('/(<%me[^%]+%>)/', $text, -1, PREG_SPLIT_DELIM_CAPTURE);

print_r($parts);

The above prints (as seen on ideone.com):

Array
(
    [0] => prefix
    [1] => <%me date() %>
    [2] => suffix
)

Related questions

• Difference between .*? and .* for regex