strcmp
strcmp Binary safe string comparison
int strcmp ( string $str1, string $str2 )
Note that this comparison is case sensitive.
Parameters
str1
The first string.
str2
The second string.
Return Values
Returns < 0 if str1 is less than str2; > 0 if str1 is greater than str2, and 0 if they are
equal.
See Also
preg_match()
strcasecmp()
substr()
stristr()
strncasecmp()
strncmp()
strstr()
strcasecmp
strcasecmp Binary safe case-insensitive string comparison
int strcasecmp ( string $str1, string $str2 )
Binary safe case-insensitive string comparison.
Return Values
Returns < 0 if str1 is less than str2; > 0 if str1 is greater than str2, and 0 if they are
equal.
Examples
Example 2463. strcasecmp() example
<?php
$var1 = "Hello";
$var2 = "hello";
if (strcasecmp($var1, $var2) == 0) {
echo '$var1 is equal to $var2 in a case-insensitive string compariso
n';
}
?>
strncmp
strncmp Binary safe string comparison of the first n characters
int strncmp ( string $str1, string $str2, int $len )
This function is similar to strcmp(), with the difference that you can specify the (upper
limit of the) number of characters from each string to be used in the comparison.
Note that this comparison is case sensitive.
str1
The first string.
str2
The second string.
len
Number of characters to use in the comparison.
Return Values
Returns < 0 if str1 is less than str2; > 0 if str1 is greater than str2, and 0 if they are
equal.
strncasecmp
strncasecmp Binary safe case-insensitive string comparison of the first n characters
int strncasecmp ( string $str1, string $str2, int $len )
This function is similar to strcasecmp(), with the difference that you can specify the
(upper limit of the) number of characters from each string to be used in the comparison.
str1
The first string.
str2
The second string.
len
The length of strings to be used in the comparison.
Return Values
Returns < 0 if str1 is less than str2; > 0 if str1 is greater than str2, and 0 if they are
equal.
strnatcmp
strnatcmp String comparisons using a "natural order" algorithm
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.
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
)
strnatcasecmp
strnatcasecmp Case insensitive string comparisons using a "natural order" algorithm
int strnatcasecmp ( string $str1, string $str2 )
This function implements a comparison algorithm that orders alphanumeric strings in the
way a human being would. The behaviour of this function is similar to strnatcmp(),
except that the comparison is not case sensitive. For more information see: Martin Pool's
Natural Order String Comparison page.
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.
