复制代码 代码如下:
<?php
/*
判断字符串是否存在的函数
*/
function strexists($haystack, $needle) {
return !(strpos($haystack, $needle) === FALSE);//注意这里的"==="
}
/*
Test
*/
$mystring = "abc";
$findme = "a";
$pos = strpos($mystring, $findme);

// Note our use of ===. Simply == would not work as expected
// because the position of "a" was the 0th (first) character.
// 简单的使用 "==" 号是不会起作用的，需要使用 "==="，因为 a 第一次出现的位置为 0
if ($pos === false) {
echo "The string "$findme" was not found in the string "$mystring"";
} else {
echo "The string "$findme" was found in the string "$mystring"";
echo " and exists at position $pos";
}

// We can search for the character, ignoring anything before the offset
// 在搜索字符的时候可以使用参数 offset 来指定偏移量
$newstring　= "abcdef abcdef";
$pos　= strpos($newstring, "a", 1); // $pos = 7, not 0
?>