如何传递额外的参数回调和访问默认参数？ [英] How to pass additional arguments to callbacks and also access default parameters?

问题描述

假设我有一个jQuery小部件的选项：

Suppose I have this as an option to a jQuery widget:

    function oneFunc()
    {
     var myVar;

       //there is some widget calling
       $.widget("ui.combobox", $.ui.autocomplete, {
                options: {
                       source: function (request, response){////doing something with myVar, request and response}
                }
       });
    }

现在我想分离出 ，response）使用回调

所以，我想要这样的：

function oneFunc()
{
     var myVar;
     //there is some widget calling
        $.widget("ui.combobox", $.ui.autocomplete, {
                options: {
                       source: myCallBack
       });
}

function myCallBack(request, response){
//I can get request and response here by default but not myVar
//doing something with myVar, request and response
}

因此，我无法访问myVar。我必须把它传递给那里。但是怎么做呢？

So, I can't access myVar. I have to pass it there. but how to do that?

EDIT：
我不想使用全局变量
code>， response 是我可以在myCallBack中获得的默认值。

I don't want to use global variables request, response are default values that I can get in myCallBack anyway.

推荐答案

如果您要访问 myVar 分离的回调函数，我将在声明中明确：

If you want to access myVar inside your separated callback function, I would make it explicit in the declaration:

function myCallBack(request, response, myVar) 
{
}

这样可以更方便地跟踪您在代码中看到它的时间稍后的。然后，你写这样的代理函数：

This makes it easier to keep track of when you see it in your code later on. Then, you write a proxy function like this:

source: function(request, response) {
    return myCallBack.call(this, request, response, myVar);
}

如果您需要更复杂的范围或 myVar 需要在两个范围内更改，您需要一个对象：

If you want a more complex scope or myVar needs to be changed in both scopes, you need an object:

var myScope = {
    myVar: null
};

// ...

source: function(request, response) {
    return myCallBack.call(this, request, response, myScope);
}

然后，在回调内：

function myCallBack(request, response, myScope) 
{
    // use myVar as myScope.myVar
}

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