PHP 中替换若干字符串字串为数组中的值，不用循环，非常高效

替换某个字符串中的一个或若干个字串为数组中某些值

php本身有自带的函数，可以不用循环非常高效的实现其效果：

实例代码：

  $phrase  = "You should eat fruits , vegetables, and fiber every day.";
  $healthy = array("fruits", "vegetables", "fiber");
  $yummy   = array("pizza", "beer","banana" );

　$newphrase = str_replace($healthy, $yummy, $phrase);

 print_r($newphrase);结果显示为：

You should eat pizza , beer, and banana every day.