CODEWITHSUNDEEP
javascript
user3161730
user3161730

Reputation: 55

Get Length of Variable

Trying to get the length of a variable territories, yet when I do territories.length it gives me 0. When I use console.log and look in the JavaScript console, it shows

child 
{
    length: 0, 
    models: Array[0], 
    _byId: Object, 
    _events: Object, 
    _listenerId: "l11"
}

So the length is 0 but when I expand that, it says that the length is9. I want it to be 9. How can I get length:9?

Upvotes: 0

Views: 2425

Answers (2)

Andrew L
Andrew L

Reputation: 1224

Length is the right property, but it depends on what kind of variable territories is. The below code for a string example outputs 9.

var territories = "my string";
var length = territories.length;
alert(length);

Since in this case territories is actually a backbone collection, you can find more information about this issue from the following question: Get collection length

Unfortunately you can't save the fetched collection data because the fetch function in backbone is asynchronous. You need to use a callback function to do whatever you need done with the length property. For more information see How to return value from an asynchronous callback function? and http://recurial.com/programming/understanding-callback-functions-in-javascript/

Upvotes: 0

scrblnrd3
scrblnrd3

Reputation: 7416

You can do this to get the number of properties in any javascript object, at least in modern browsers:

Object.keys(myObj).length;

You could also do this manually, like this

Object.prototype.length=function(){
    var count=0;
    for(var i in this){
        if(this.hasOwnProperty(i)){
            count++;
        }
    }
    return count;
}

Upvotes: 1

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