strnatcasecmp
If you want to compare $_SESSION variables to a string use this
<?php
if(isset($_SESSION['usertype']))
{
echo "usertype " .$_SESSION['usertype'];
$ut = $_SESSION['usertype'];
if(strnatcmp($ut,"admin"))
{
echo "hello admin";
}
}
?>
strnatcmp
(PHP 4, PHP 5)
strnatcmp — String comparisons using a "natural order" algorithm
Description
int strnatcmp
( string
$str1
, string $str2
)This function implements a comparison algorithm that orders alphanumeric strings in the way a human being would, this is described as a "natural ordering". Note that this comparison is case sensitive.
Parameters
-
str1 -
The first string.
-
str2 -
The second string.
Return Values
Similar to other string comparison functions, this one returns < 0 if
str1 is less than str2; >
0 if str1 is greater than
str2, and 0 if they are equal.
Examples
An example of the difference between this algorithm and the regular computer string sorting algorithms (used in strcmp()) can be seen below:
<?php
$arr1 = $arr2 = array("img12.png", "img10.png", "img2.png", "img1.png");
echo "Standard string comparison\n";
usort($arr1, "strcmp");
print_r($arr1);
echo "\nNatural order string comparison\n";
usort($arr2, "strnatcmp");
print_r($arr2);
?>
The above example will output:
Standard string comparison
Array
(
[0] => img1.png
[1] => img10.png
[2] => img12.png
[3] => img2.png
)
Natural order string comparison
Array
(
[0] => img1.png
[1] => img2.png
[2] => img10.png
[3] => img12.png
)
See Also
- preg_match() - Perform a regular expression match
- strcasecmp() - Binary safe case-insensitive string comparison
- substr() - Return part of a string
- stristr() - Case-insensitive strstr
- strcmp() - Binary safe string comparison
- strncmp() - Binary safe string comparison of the first n characters
- strncasecmp() - Binary safe case-insensitive string comparison of the first n characters
- strnatcasecmp() - Case insensitive string comparisons using a "natural order" algorithm
- strstr() - Find the first occurrence of a string
- natsort() - Sort an array using a "natural order" algorithm
- natcasesort() - Sort an array using a case insensitive "natural order" algorithm
add a note
User Contributed Notes
strnatcmp - [2 notes]
Zero ¶
2 years ago
thomas at uninet dot se ¶
6 years ago
There seems to be a bug in the localization for strnatcmp and strnatcasecmp. I searched the reported bugs and found a few entries which were up to four years old (but the problem still exists when using swedish characters).
These functions might work instead.
<?php
function _strnatcasecmp($left, $right) {
return _strnatcmp(strtolower($left), strtolower($right));
}
function _strnatcmp($left, $right) {
while((strlen($left) > 0) && (strlen($right) > 0)) {
if(preg_match('/^([^0-9]*)([0-9].*)$/Us', $left, $lMatch)) {
$lTest = $lMatch[1];
$left = $lMatch[2];
} else {
$lTest = $left;
$left = '';
}
if(preg_match('/^([^0-9]*)([0-9].*)$/Us', $right, $rMatch)) {
$rTest = $rMatch[1];
$right = $rMatch[2];
} else {
$rTest = $right;
$right = '';
}
$test = strcmp($lTest, $rTest);
if($test != 0) {
return $test;
}
if(preg_match('/^([0-9]+)([^0-9].*)?$/Us', $left, $lMatch)) {
$lTest = intval($lMatch[1]);
$left = $lMatch[2];
} else {
$lTest = 0;
}
if(preg_match('/^([0-9]+)([^0-9].*)?$/Us', $right, $rMatch)) {
$rTest = intval($rMatch[1]);
$right = $rMatch[2];
} else {
$rTest = 0;
}
$test = $lTest - $rTest;
if($test != 0) {
return $test;
}
}
return strcmp($left, $right);
}
?>
The code is not optimized. It was just made to solve my problem.