Return multiple values in JavaScript?

I am trying to return two values in JavaScript. Is that possible?

var newCodes = function() {  
    var dCodes = fg.codecsCodes.rs;
    var dCodes2 = fg.codecsCodes2.rs;
    return dCodes, dCodes2;
};

---

No, but you could return an array containing your values:

var newCodes = function() {
    var dCodes = fg.codecsCodes.rs;
    var dCodes2 = fg.codecsCodes2.rs;
    return [dCodes, dCodes2];
};

Then you can access them like so:

var codes = newCodes();
var dCodes = codes[0];
var dCodes2 = codes[1];

If you want to put "labels" on each of the returned values (easier to maintain), you can return an object:

var newCodes = function() {
    var dCodes = fg.codecsCodes.rs;
    var dCodes2 = fg.codecsCodes2.rs;
    return {
        dCodes: dCodes,
        dCodes2: dCodes2
    };
};

And to access them:

var codes = newCodes();
var dCodes = codes.dCodes;
var dCodes2 = codes.dCodes2;

---

You can do this from Javascript 1.7 onwards using "destructuring assignments". Note that these are not available in older Javascript versions (meaning — neither with ECMAScript 3rd nor 5th editions).

It allows you to assign to 1+ variables simultaneously:

var [x, y] = [1, 2];
x; // 1
y; // 2

// or

[x, y] = (function(){ return [3, 4]; })();
x; // 3
y; // 4

You can also use object destructuring combined with property value shorthand to name the return values in an object and pick out the ones you want:

let {baz, foo} = (function(){ return {foo: 3, bar: 500, baz: 40} })();
baz; // 40
foo; // 3

And by the way, don't be fooled by the fact that ECMAScript allows you to return 1, 2, ... . What really happens there is not what might seem. An expression in return statement — 1, 2, 3 — is nothing but a comma operator applied to numeric literals ( 1 , 2 , and 3 ) sequentially, which eventually evaluates to the value of its last expression — 3 . That's why return 1, 2, 3 is functionally identical to nothing more but return 3 .

return 1, 2, 3;
// becomes
return 2, 3;
// becomes
return 3;

---

只需返回一个对象文字

function newCodes(){
    var dCodes = fg.codecsCodes.rs; // Linked ICDs  
    var dCodes2 = fg.codecsCodes2.rs; //Linked CPTs       
    return {
        dCodes: dCodes, 
        dCodes2: dCodes2
    };  
}


var result = newCodes();
alert(result.dCodes);
alert(result.dCodes2);

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