Q. How do I find out if a string stored in a variable contains a particular substring using PHP? How do I find out (extract) first 5 character of a particular string using Apache and PHP?
A. You need to use the following php functions:
a] strpos() : Find position of first occurrence of a string
b] substr() : Return part of a string
c] substr_replace() : Replacing a substring
Find position of first occurrence of a string with strpos()
Find out if $input contains a # symbol or not:
<?php if (strpos($input, '#') === true ) { print '# symbol found in input'; } else{ print 'There was no # symbol found in input'; } ?>
Extracting a substring with substr()
<?php $input = "nixCraft blog"; // substr syntax // $substring = substr($string,$start,$length); // Get first 5 chars of $input $data = substr($input,0,5); print $data; ?>
This is useful for finding out usernames and other data.
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