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$_FILE()这种格式到底是系统函数还是预定义变量,我看php手册是预定义变量,但是有的课程讲师讲的是系统函数,谁为正?


回复讨论(解决方案)

$_FILE怎么可能是系统函数呢,就是预定义的一个数组,首先分清楚什么是函数,什么是变量吧!

预定义变量,当然是手册正确
即使翻译的在不准确,也不可能译作“函数”

$_FILE怎么可能是系统函数呢,就是预定义的一个数组,首先分清楚什么是函数,什么是变量吧!
预定义变量怎么可以传递参数的啊?在我的印象中变量就是变量为何可以传递参数?谢谢

没有明白你说的传递参数是什么意思,你能列举个例子详细说明一下你说的传递参数的例子么?

如果你说的是$_FILE['tmp']这种格式的话,那不叫传递参数,只是在数组中获取tmp元素的值。

没有明白你说的传递参数是什么意思,你能列举个例子详细说明一下你说的传递参数的例子么?

如果你说的是$_FILE['tmp']这种格式的话,那不叫传递参数,只是在数组中获取tmp元素的值。
谢谢,你的讲解很透彻!

if (is_uploaded_file($_FILES['upfile']['tmp_name'])){

$upfile=$_FILES["upfile"];

$name = $upfile["name"];
$type = $upfile["type"];
$size = $upfile["size"];
$tmp_name = $upfile["tmp_name"];
$error = $upfile["error"];


switch ($type) {
case 'image/pjpeg' : $ok=1;
break;
case 'image/jpeg' : $ok=1;
break;
case 'image/gif' : $ok=1;
break;
case 'image/png' : $ok=1;
break;
}

if($ok && $error=='0'){
 move_uploaded_file($tmp_name,'up/'.$name);
 echo "上传成功";
}
}


?>


  上传文件:
  
  

 


这里面的代码$upfile=$_FILES["upfile"];   这个upfile算不算传递参数?

算,传入的参数!

算,传入的参数!
版主,从这个层面上说$_FILE也可以算是函数,是吧?

楼主有点咬文嚼字了,上面两位已经解释得够清楚了。建议去翻翻手册。

楼主有点咬文嚼字了,上面两位已经解释得够清楚了。建议去翻翻手册。

呵呵,我是新手,追求真知也没什么不好,业余学生学习难啊,呵呵!

楼主有点咬文嚼字了,上面两位已经解释得够清楚了。建议去翻翻手册。
新手,不太懂,所以要弄清楚!


楼主有点咬文嚼字了,上面两位已经解释得够清楚了。建议去翻翻手册。
新手,不太懂,所以要弄清楚!

参数的概念通常都是函数关联在一起,在php源代码的范畴来说,$a['b']不能算作传参,因为是一个取元素运算,不算函数调用。但是说到源代码也要被php执行引擎来执行的范畴来说,$a['b']在底层实现也是要靠函数来执行的,这样也可以算作传参。



楼主有点咬文嚼字了,上面两位已经解释得够清楚了。建议去翻翻手册。
新手,不太懂,所以要弄清楚!

参数的概念通常都是函数关联在一起,在php源代码的范畴来说,$a['b']不能算作传参,因为是一个取元素运算,不算函数调用。但是说到源代码也要被php执行引擎来执行的范畴来说,$a['b']在底层实现也是要靠函数来执行的,这样也可以算作传参。


谢谢楼主!

预定义变量

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