Question

I have strings that have the following pattern. Some text on some more text before some text.

How do I find

• the position of the word “before” and remove it with anything after it,
• and the position of the word ” on ” and remove it with anything before it?

Answer 1

Regular expressions are overkill for this. Just do a substring from where you find “on” to where you find “before”:

$str = 'Some text on some more text before some text';

// Find " on "
$start = strpos($str, " on ");

// Check for errors
// Note the 3 ='s
if($start === FALSE) {
    // Error occurred, do something
}
$start += 4; // Go after "on"

// Find " before "
$end = strpos($str, " before ", $start);

// Check for errors
// Note the 3 ='s
if($end === FALSE) {
    // Error occurred, do something
}

// Get just the part we want
$length = $end - $start;
$result = substr($str, $start, $end - $start);