<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<?php
$str1="str2";
$str2="str10";
$str3="yj";
$str4="YJ";
echo strcmp($str1,$str2);
echo strnatcmp($str1,$str2);
echo strcmp($str3,$str4);
echo strcasecmp($str3,$str4);
echo strnatcmp($str3,$str4);
echo strnatcasecmp($str3,$str4);
?>
</body>
</html>
strcmp,strnatcmp是大小写敏感的 strcasecmp,strnatcmp是大小写不敏感的
strnatcmp,strnatcasecmp是按照数理逻辑大家区分的,strcmp,strcasecmp是按照一个字符一个字符比较的
如果两个字符串相等,返回0。如果第一个字符串比第二个字符串大,则返回正数,如果第一个字符串比第二个字符串小,则返回负数
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<body>
<?php
$str1="str2";
$str2="str10";
$str3="yj";
$str4="YJ"."<br>";
$str5="i am happy";
$str6="i am serenade";
echo strncmp($str5,$str6,8);
?>
</body>
</html>
strncmp(字符串一,字符串二,n)这个是比较两个字符串前n个字符是否相等