Question

我有以下JavaScript代码：

var objSample = {
   variable: 10,
   func1 : function(){
       someJQueryPlugin(1, function(){
             this.variable; // this doesn't work, don't have access
       });
    }
}

我有两个问题：

1）如何创建变量的实例，以便我可以拥有两个独立的对象，每个对象都有自己唯一的变量值？

示例：

var obj1 = new objSample();
obj1.variable = 1;

var obj2 = new objSample();
obj2.variable = 2;

2）如何从对象中的函数内的jQuery插件访问匿名函数内的变量。通过this没有帮助。

Answer 1

var objSample = function(){
  this.variable = 10
   this.func1 = function(){
       someJQueryPlugin(1, function(){
             this.variable; <-- this doesn't work, don't have access
       });
    }
}

你也可以用params扩展构造函数

 var objSample = function(options){
  this.variable = options.val
   this.func1 = function(){
       someJQueryPlugin(1, function(){
             this.variable; <-- this doesn't work, don't have access
       });
    }
}
var obj1  = new objSample ({val:1})
var obj2  = new objSample ({val:2})

并从不同上下文中的回调访问this，将其包含在某个变量中。所以最终代码如下：

 var objSample = function(options){
      var self = this;
      self.variable = options.val
       self.func1 = function(){
           someJQueryPlugin(1, function(){
                 self.variable;
           });
        }
    }

Answer 2

您需要将代码从对象文字更改为构造函数，并确保在this函数中引用正确的func1。

function ObjSample() {
  this.variable = 10;
  this.func1 = function () {
    var _this = this;
    someJQueryPlugin(1, function () {
      _this.variable;
    });
  }
}

DEMO

在Javascript中创建变量的实例并在匿名函数中访问变量

2 个答案: