javascript - 如何从内部嵌套函数调用父函数？

Question

我有一个简单的 jQueryready事件，它通过调用对象中的 a 函数来初始化视图setupView。

我的问题是，setSomethingImportant从init函数调用函数的适当方法是什么，如下所示？

init由于调用是从与函数不同的执行上下文进行的，this.setSomethingImportant()因此不起作用。但是，如果我使用setupView.setSomethingImportant(). 我遇到的问题是，如果 var name ( setupView) 发生更改，我也必须更改代码主体。

   (function() {        
        $(document).ready(function() {              
            setupView.init();               
        });     
         var setupView = {          
            currentState : "CT",            
            init : function () {
               $("#externalProtocol").change( function () {
                    console.log("Changed =" + $(this).val());
                    setSomethingImportant(); 
                               // Question ? how to call a method in the setupView object   
                });         
             },         
             setSomethingImportant : function () {
                 this.currentState="TC";    
                 console.log("Something has changed :" + this.currentState );
             }      
         }  
 }(jQuery);

Answer 1

存储this到变量中：

var setupView = {
    currentState: "CT",
    init: function() {
        // Keep a reference to 'this'
        var self = this;
        $("#externalProtocol").change(function() {
            console.log("Changed =" + $(this).val());

            // Use the old 'this'
            self.setSomethingImportant();
        });
    },
    setSomethingImportant: function() {
        this.currentState = "TC";
        console.log("Something has changed :" + this.currentState);
    }
};

请参阅工作演示。

Answer 2

只需单独声明该函数，然后像这样调用：

function setSomethingImportant(context) {
    context.currentState="TC";    
    console.log("Something has changed :" + context.currentState );
};

(function() {        
        $(document).ready(function() {              
            setupView.init();               
        });     
         var setupView = {          
            currentState : "CT",            
            init : function () {
               $("#externalProtocol").change( function () {
                    console.log("Changed =" + $(this).val());
                    setSomethingImportant(this); 
                               // Question ? how to call a method in the setupView object   
                });         
             },         
             setSomethingImportant : function () {
                 setSomethingImportant(this);
             }      
         }  
}(jQuery);

Answer 3

Please note that I changed my original solution. I am now passing data to the event handler using even.data.

(function() {        
    $(document).ready(function() {              
        setupView.init();               
    });     
    var setupView = {          
        currentState : "CT",            
        init : function () {
            $("#externalProtocol").change({ _this: this }, function (event) {
                console.log("Changed =" + $(this).val());
                event.data._this.setSomethingImportant(); 
            });         
        },         
        setSomethingImportant : function () {
            this.currentState="TC";    
            console.log("Something has changed :" + this.currentState );
        }      
    }  
 }(jQuery);