PHP strnatcmp()Functions

PHP String 参考手册PHP String Reference Manual

Examples

Compare two strings using the "natural" algorithm (case-sensitive):

<?php
echo strnatcmp("2Hello world!","10Hello world!");
echo "<br>";
echo strnatcmp("10Hello world!","2Hello world!");
?>

Run Example »

Definition and Usage

The strnatcmp() function compares two strings using a "natural" algorithm (case-sensitive).

In natural algorithm, the number 2 is less than the number 10. In computer sorting, 10 is less than 2, because the first digit in 10 is less than 2.

Note:This function is case-sensitive.

Syntax

strnatcmp(string1,string2)

Parameters Description
string1 Required. Specifies the first string to compare.
string2 Required. Specifies the second string to compare.

Technical Details

Return Value: This function returns:
  • 0 - if the two strings are equal
  • <0 - if string1 is less than string2
  • >0 - if string1 is greater than string2
PHP Version: 4+

More Examples

Example 1

The difference between the natural algorithm (strnatcmp) and the regular computer string sorting algorithm (strcmp):

<?php
$arr1 = $arr2 = array("pic1","pic2","pic10","pic01","pic100","pic20","pic30","pic200");
echo "Standard string comparison"."<br>";
usort($arr1,"strcmp");

print_r($arr1);
echo "<br>";

echo "Natural order string comparison"."<br>";
usort($arr2,"strnatcmp");

print_r($arr2);
?>

Run Example »

PHP String 参考手册PHP String Reference Manual Other Extensions