How to trim the content of a PHP string before a certain point

In PHP, the substr() function can be used to extract content from a string. This function takes three parameters: the string, the starting position, and the length to be extracted.

Below is an example code demonstrating how to extract content before a specific string.

$str = "Hello, World!";
$substr = "Hello";

$result = substr($str, 0, strpos($str, $substr));
echo $result;

The output result is an empty string because there is no other content before “Hello”.

Please note, the code above assumes that the content to be extracted appears only once in the original string. If the content appears multiple times, you can use the strpos() function combined with a loop for processing.