如何正确传递我的范围以查找变量

Question

i was trying to use the javascript APPLY function to pass scope from 1 function to another, but it seems that i might be doing it wrong?

Here is a fiddle if you need it: http://jsfiddle.net/C8APz/

Here is my code:

function a(){
    var x = "hello";
    b.apply(this, []);
}

 function b(){
    console.log("x: ", x);
}

a();

i was thinking that while the scope is passed, the variables / variable reference are not.

Is there a way to do something like this without defining Globals?

Should i add the data to the actual part of it, such as this.x = x; ? and then in the other function just fetch it? var x = this.x;

function a(){
    var x = "hello";
    this.x = x;
    b.apply(this, []);
}

 function b(){
    var x = this.x;
    console.log("x: ", x);
}

a();

Edit: It seems that the second example assigns in the global scope, which isnt good, and with the scope, i was attempting to pass an understanding of context to. It seems that you really have to define a context before you pass it, otherwise, for the most part this refers to window

Answer 1

You cannot pass scope around.

You can either move the function declaration for b inside the function declaration for a so that the scope is right to start with, or you can pass the variables you care about using arguments.

---

function a(){
    var x = "hello";
    b();

    function b(){
        console.log("x: ", x);
    }
}

a();

---

function a(){
    var x = "hello";
    b(x);
}

function b(x){
    console.log("x: ", x);
}

a();

Answer 2

Declare var x; out of the function body...

var x;
function a(){
    x = "hello";
    b.apply(this, []);
}

function b(){
    //a.apply(this,[]);
    console.log("x: ", x);
}

a();