w3resource

PHP: substr_compare() function

Description

The substr_compare() function is used to compare two strings from a given starting position in the main string.

Version:

(PHP 5)

Syntax:

substr_compare(main_string, compare_string, star_pos, length, case_insensitivity)

Parameters:

Name Description Required /
Optional		 Type
main_string The main string. Required String
compare_string The string to be compared. Required String
star_pos The starting position in the main string. Required Integer
length A positive number : Start at the specified position in the string.
A negative number : Start at a specified position from the end of the string.		 Optional Integer
case_insensitivity If set TRUE comparison is case insensitive. Optional Boolean

Return value:

0 : If two main_string=compare_string
<0 : if the length of the main_string from the starting position is less than the compare_string
>0 : if the length of the main_string from the starting position is greater than the compare_string.

Value Type: Integer.

Pictorial Presentation

string_substr_compare

Example: 

<?php
echo substr_compare('uvwxyz', 'uv', 1, 2).'<br>';
echo substr_compare('uvwxyz', 'uvw', 1, 2).'<br>';
echo substr_compare('uvwxyz', 'uv', -2, 2).'<br>';
echo substr_compare('uvwxyz', 'xy', 1, 2).'<br>';
echo substr_compare('uvwxyz', 'xyz', -3, 3).'<br>';
?>

Output: 

1
1
4
-2
0

View the example in the browser

See also

PHP Function Reference

Previous: strtr
Next: substr_count



PHP: Tips of the Day

Get the full URL in PHP

Have a look at $_SERVER['REQUEST_URI'], i.e.

Example:

$actual_link = "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

(Note that the double quoted string syntax is perfectly correct)

If you want to support both HTTP and HTTPS, you can use

$actual_link = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on' ? "https" : "http") . "://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

Editor's note: using this code has security implications. The client can set HTTP_HOST and REQUEST_URI to any arbitrary value it wants.

Ref : https://bit.ly/2ZYItNJ