(PHP 4, PHP 5, PHP 7)
require_once 锟斤拷锟斤拷 require 锟斤拷锟斤拷锟饺拷锟酵拷锟轿ㄒ伙拷锟斤拷锟斤拷锟� PHP 锟斤拷锟斤拷锟斤拷募锟斤拷欠锟斤拷丫锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟斤拷锟津不伙拷锟劫次帮拷锟斤拷锟斤拷
锟轿硷拷 include_once 锟斤拷锟侥碉拷锟斤拷锟斤拷锟� _once 锟侥猴拷锟藉，锟斤拷锟斤拷锟斤拷锟矫伙拷锟� _once 时锟斤拷锟斤拷什么锟斤拷同锟斤拷