PHP Cookbook

13.9. Reading Records with a Pattern Separator

Problem

You want to read in records from a file, in which each record is separated by a pattern you can match with a regular expression.

Solution

Read the entire file into a string and then split on the regular expression:

$filename = '/path/to/your/file.txt';
$fh = fopen($filename, 'r') or die($php_errormsg);
$contents = fread($fh, filesize($filename));
fclose($fh);

$records = preg_split('/[0-9]+\) /', $contents);

Discussion

This breaks apart a numbered list and places the individual list items into array elements. So, if you have a list like this:

1) Gödel 
2) Escher
3) Bach

You end up with a four-element array, with an empty opening element. That’s because preg_split( ) assumes the delimiters are between items, but in this case, the numbers are before items:

               Array
               (
                   [0] => 
                   [1] => Gödel
                   [2] => Escher
                   [3] => Bach
               )

From one point of view, this can be a feature, not a bug, since the nth element holds the nth item. But, to compact the array, you can eliminate the first element:

$records = preg_split('/[0-9]+\) /', $contents);
array_shift($records);

Another modification you might want is to strip new lines from the elements and substitute the empty string instead:

$records = preg_split('/[0-9]+\) /', str_replace("\n",'',$contents));
array_shift($records);

PHP doesn’t allow you to change the input record separator to anything other than a newline, so this technique is also useful for breaking apart records divided by strings. However, if you ...