String to array, split by new lines and brackets

Question

I have large string block which I need to split into arrays based on if they're wrapped in brackets or separated by new lines.

Input:

[this is block
this is also same "block"
this is same block

another same block]
new block!
another new block!
[this is new block
this is also a new block]

One of the many things I've tried:

$block_lines = preg_split('/\[([^]]+)\]|\r/', $block_content);

Expected result:

Array
(
  [0] => 'this is block
  this is also same "block"
  this is same block

  another same block'
  [1] => 'new block!'
  [2] => 'another new block!'
  [3] => 'this is new block
  this is also a new block'
)

Actual result:

Array
(
  [0] => 'new block!'
  [1] => 'another new block!'
  [2] => ''
)

Answer 1

You can use this regex in preg_split:

/\[([^]]+)]|\R/

It splits the string on either a string of characters inside [ and ], or on a newline. By using the PREG_SPLIT_DELIM_CAPTURE flag, we can capture the contents of the [] as well:

$string = '[this is block
this is also same "block"
this is same block

another same block]
new block!
another new block!
[this is new block
this is also a new block]';
print_r(preg_split('/\[([^]]+)]|\R/', $string, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE));

Output:

Array ( 
    [0] => this is block 
this is also same "block" 
this is same block

another same block
    [1] => new block!
    [2] => another new block!
    [3] => this is new block
this is also a new block
)

Demo on 3v4l.org