php多个字符串替换成同一个的解决方法

　　<?php

　　$name = 'Today 3? , very/ cold';

　　$name = strtolower($name);

　　//$name = preg_replace('/[^a-z0-9\s]/','',$name);

　　$name = preg_replace('/[\.\s+\?,\/"]/','_',$name); //change spaces

　　echo $name;

　　?>

　　$name = preg_replace('/[\.\s+\?,\/"]/','_',$name); //change spaces