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HomeBackend DevelopmentPHP Tutorialphp中变量前加&、@等符号是什么意思?

如:$this->config = &$config;
如:if(@$_POST['add']){...}
还有这个
static function &instance() {
static $object;
if(empty($object)) {
$object = new self();
}
return $object;
}
分别都是什么意思和作用,请说明,感谢!!!


回复讨论(解决方案)

@ 是忽略错误提示,使其错误消息不会显示在程序里,&是取地址,也可以说是地址引用.不知道准不准确

@ 是忽略错误提示,使其错误消息不会显示在程序里,&是取地址,也可以说是地址引用.不知道准不准确

是这个意思.

	//@用于抑制警告输出,通常用在PHP数据库连接数据库这里,如		@mysql_connect(self::$dbhost,self::$dbuser,self::$dbpassword);	//&为引用变量 or 函数地址等,这个&跟C语言的指针有相似之处,	//但并不相同,C语言的指针指向内存	//而PHP指的是不同的名字访问同一个变量内容.如	$a=5;	$b=&$a;	echo $b;

错误御制符..

引用 1 楼 suconghou 的回复:@ 是忽略错误提示,使其错误消息不会显示在程序里,&是取地址,也可以说是地址引用.不知道准不准确

是这个意思.
确实是这个意思....

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