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class Images{
var $inputName;                 //控件名
var $allowType = array(
'image/gif','image/jpg','image/jpeg','image/png','image/x-png','image/pjpeg'
);                            //上传类型
var $allowSize = 2097152; //限制大小
var $saveDir = $_SERVER['DOCUMENT_ROOT']."/upfiles/user";      //保存目录
var $isRename = true;               //是否重命名,默认为true
var $errID = 0;                     //错误代码,默认为0
var $errMsg = "";                   //错误信息
var $savePath = "";                 //保存路径


var $saveDir = $_SERVER['DOCUMENT_ROOT']."/upfiles/user";      //保存目录
这么写错误?那应该怎么写啊




回复讨论(解决方案)


var_dump($_SERVER['DOCUMENT_ROOT']);看看有没有内容
没有的话。 用var_dump($_SERVER)看一下。
如果有问题
直接写成常量吧

是写发有错误!写法 esshop 直接提示错误的写法!

$saveDir = $_SERVER['DOCUMENT_ROOT']."/upfiles/user";    去掉var看一下

提示什么错误了?

类定义中,属性不能是未确定的值
你可以在构造函数中赋值

class Images{
  var $saveDir;
  function Image() {
    $this->saveDir = $_SERVER['DOCUMENT_ROOT']."/upfiles/user";      //保存目录
  }

 

呵呵,好内容啊。。。。。

类定义中,属性不能是未确定的值
你可以在构造函数中赋值

class Images{
  var $saveDir;
  function Image() {
    $this->saveDir = $_SERVER['DOCUMENT_ROOT']."/upfiles/user";      //保存目录
  }

  
正解,类的属性,在定义的时候只能是具体的值,不能是实例化之类的,事先不知道的内容。

class的属性只能定义数值常量(或者叫数值字面量)

例如 1 就是一个数值常量,array(1) 也是数值常量, 而 1 + 1 就不是,因为是表达式运算

是不是斜杠反了,我不确定,我以前做的好像是和你的斜杠反的。

'./application/excels/';
我在项目中是这样写的、

5楼老大给出你答案了,类成员变量在定义时值只能是个常量值,并且不能做任何运算。

我记得这也是个规范问题,定义类成员变量时都不应该直接赋值。而应该都放在构造函数中赋值。

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