截取某个字符之前的字符串

// 如下为截取 "-" 字符前的字符串

$str = "hello-world"; 
$new_string = substr( $str, 0, strrpos($str, '-') );
echo $new_string;   // 输出 "hello" 

字符串替换

php替换多个字符串 str_replace 函数，可以传入要删除替换的字符串

echo str_replace(array("m","i"), array("n","z"), "my name is jim!")  

echo str_replace(array('m', 'i'), 'n', "my name is jim!");  

$vowels = array("a", "e", "i", "o", "u", "A", "E", "I", "O", "U");   $onlyconsonants = str_replace($vowels, "", "Hello World of PHP");   echo $onlyconsonants;  

反转字符串

strrev( $string )

返回 string 反转后的字符串。