javascript function ignores return statement

Question

I have a function returning null by default, and another value by condition.

var getName = function(boxid){
    var boxes = localStorage.getItem("boxes");
    if((boxes != "" )&& (typeof boxes != "undefined") &&( boxes != null))
    {
        boxes = JSON.parse(boxes);
        boxes.forEach(function(box){
            if(box.id == boxid)
            {
                console.log("box.name: "+ box.name+ " boxid: "+ box.id+ " : "+ boxid);
                return box.name;
            }
        });
    }
    return null;
};

the correct array-entry gets found. but the return statemant doesn't return it, it's ignored.

I just call it alert(getName(boxid)); Isn't the return statement of the if-condition ending the function? — marcel
– marcel, Commented Feb 24, 2014 at 9:00
possible duplicate of How to short circuit Array.forEach like calling break? - especially the SECOND answer: shiny-new-toy disease — mplungjan
– mplungjan, Commented Feb 24, 2014 at 9:02

kaspermoerch · Accepted Answer · 2014-02-24 09:15:05Z

5

The reason your return statement isn't working is because it is local to the forEach's callback, and not related to your getName-function.

You should use a normal for-loop instead:

var getName = function(boxid){
    var boxes = localStorage.getItem("boxes");
    if((boxes != "" )&& (typeof boxes != "undefined") &&( boxes != null))
    {
        boxes = JSON.parse(boxes);
        for(var i = 0; i < boxes.length; i++) {
            if(boxes[i].id == boxid)
            {
                console.log("boxName: "+ boxes[i].name+ " boxID: "+ boxes[i].id+ " : "+ boxid);
                return boxes[i].name;
            }
        };
    }
    return null;
};

edited Feb 24, 2014 at 9:15

answered Feb 24, 2014 at 9:03

kaspermoerch

16.7k4 gold badges48 silver badges69 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

xdazz · Accepted Answer · 2014-02-24 09:01:19Z

1

Because they are in different scope.

You could use filter and map function:

boxes = JSON.parse(boxes);

// the result will be an array of box name
return boxes.filter(function(box){
    return box.id = boxid;
}).map(function(box) {
    return box.name;
});

// if the box id is unqic, then just get the first one.

answered Feb 24, 2014 at 9:01

xdazz

161k38 gold badges255 silver badges278 bronze badges

1 Comment

marcel Over a year ago

it returns the entire boxex-content.

francadaval · Accepted Answer · 2014-02-24 09:04:32Z

1

The return box.name; is for the function inside forEach.

The function getName only have return null;

answered Feb 24, 2014 at 9:04

francadaval

2,5313 gold badges26 silver badges38 bronze badges

Collectives™ on Stack Overflow

javascript function ignores return statement

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related