substr_compare
(PHP 5, PHP 7, PHP 8)
substr_compare — Binary safe comparison of two strings from an offset, up to length characters
Description
substr_compare(
string $haystack,
string $needle,
int $offset,
?int $length = null,
bool $case_insensitive = false
): intsubstr_compare() compares haystack from position offset with needle up to length characters.
Parameters
haystack-
The main string being compared.
needle-
The secondary string being compared.
offset-
The 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
needlecompared to the length ofhaystackminus theoffset. case_insensitive-
If
case_insensitiveistrue, comparison is case insensitive.
Return Values
Returns -1 if haystack from position offset is less than needle, 1 if it is greater than needle, 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 haystack, or the length is set and is less than 0, substr_compare() prints a warning and returns false.
Changelog
| Version | Description |
|---|---|
| 8.2.0 | This function now returns -1 or 1, where it previously returned a negative or positive number. |
| 8.0.0 | length is nullable now. |
| 7.2.18, 7.3.5 | offset may now be equal to the length of haystack. |
Examples
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
?>See Also
- strncmp() - Binary safe string comparison of the first n characters
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.substr-compare.php