(PHP 5, PHP 7)
substr_compare — Binary safe comparison of two strings from an offset, up to length characters
$main_str
, string $str
, int $offset
[, int $length
[, bool $case_insensitivity = FALSE
]] ) : int
substr_compare() compares main_str
from position offset with str
up to length characters.
main_strThe main string being compared.
strThe secondary string being compared.
offsetThe start position for the comparison. If negative, it starts counting from the end of the string.
length
The length of the comparison. The default value is the largest of the
length of the str compared to the length of
main_str minus the
offset.
case_insensitivity
If case_insensitivity is TRUE, comparison is
case insensitive.
Returns < 0 if main_str from position
offset is less than str, >
0 if it is greater than str, and 0 if they are equal.
If offset is equal to (prior to PHP 7.2.18, 7.3.5) or
greater than the length of main_str, or the
length is set and is less than 0,
(or, prior to PHP 5.5.11, less than 1)
substr_compare() prints a warning and returns
FALSE.
| Version | Description |
|---|---|
| 7.2.18, 7.3.5 |
offset may now be equal to the length of main_str.
|
| 5.5.11 |
length may now be 0.
|
| 5.1.0 |
Added the possibility to use a negative offset.
|
Example #1 A substr_compare() example
<?php
echo substr_compare("abcde", "bc", 1, 2); // 0
echo substr_compare("abcde", "de", -2, 2); // 0
echo substr_compare("abcde", "bcg", 1, 2); // 0
echo substr_compare("abcde", "BC", 1, 2, true); // 0
echo substr_compare("abcde", "bc", 1, 3); // 1
echo substr_compare("abcde", "cd", 1, 2); // -1
echo substr_compare("abcde", "abc", 5, 1); // warning
?>