JavaScript：将函数存储在对象中，但在本地上下文中执行

Question

I have an object like this:

objectx = {
    1: {
        name: "first",
        loadFunction: function() { 
            $(target).load("http://stackoverflow.com #question", function() {
                // do something else
            });
        }
    },
    2: {
        name: "second",
        loadFunction: function() { 
            $(target).load("http://stackoverflow.com #answer", function() {
                // do something else
            });
        }
    }
}

When I call the functions with objectx[1].loadFunction(), they don't have the local context, so I would have to pass everything as argument or make my variables global. For example:

function doSomething() {
    var target; // this variable holds a reference to a DOM object

    objectx[1].loadFunction()
}

target is not defined

How do I execute the functions so that they are aware of the context they are called from?

Answer 1

This is not possible (the way you do it), due to how lexical scope works in JavaScript.

You want a function argument, plain and simple. Writing functions that depend on global state is bad style anyway.

var objectx = {
    1: {
        name: "first",
        loadFunction: function(target) { 
            $(target).load("http://stackoverflow.com #question", function() {
                // do something else
            });
        }
    }
}

and

function doSomething() {
    var target; // this variable holds a reference to a DOM object

    objectx[1].loadFunction(target);
}

Done.

Answer 2

This is impossible in JavaScript. JS uses lexical scoping . What you seem to be looking for is dynamic scope.

The best you can do is either pass arguments, define it in scope, or use a global variable (less than recommended).