Retrieving labels from JSON objects in javascript

Question

Say I have JSON data as below:

var db=[
        {"name":"John Doe","age":25},
        {"name":"John Doe 2","age":21}
       ]

I know how to retrieve data from the JSON object using js/jquery. What I need is to get the value of the labels, i.e. I want to retrieve the "name" and the "age" from the object. I don't actually want to retrieve the values "John Doe" and 25 (I can already do that), instead I want the labels.

Say the JSON object has about 5 data with 10 fields each. I need to display the JSON in table form dynamically which I can already do. Since the JSON may be any set of values, I won't know what label to put in the <th></th> cells of the table. So I need a way to get the labels.

Using a pseudo code:

var db=[
        {"name":"John Doe","age":25},
        {"name":"John Doe 2","age":21}
       ]    
for i in db{
    for j in db[i]{
          console.log(db[i][j].label+":"db[i][j])
    }  
}
//db[i][j].label doesn't really work

The output should be:

name: John Doe

age: 25

name: John Doe

age: 21

Is there a JavaScript or jQuery function to do so or some other method to retrieve the required data?

Once loaded the JSON data is just an object. You can just iterate over the properties/keys of the object. — iCollect.it Ltd, Aug 08 '14 at 13:12
Possible duplicate of http://stackoverflow.com/questions/208016/how-to-list-the-properties-of-a-javascript-object — vivek_ganesan, Aug 08 '14 at 13:12
possible duplicate of [Javascript: Getting all existing keys in a JSON array](http://stackoverflow.com/questions/9767133/javascript-getting-all-existing-keys-in-a-json-array) — Patrick Q, Aug 08 '14 at 13:13

score 5 · Accepted Answer · answered Aug 08 '14 at 13:13

5

You're already fetching the property name (which you are calling "label"). You need it to get the property's value out of the object.

So, it's just j.

console.log(j + ":" + db[i][j]);

answered Aug 08 '14 at 13:13

Quentin

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score 1 · Answer 2 · answered Aug 08 '14 at 13:13

Once loaded the JSON data is just an object (in your case an array of objects). You can just iterate over the properties/keys of each single object.

e.g.

$.each(db, function(index, object) {
    for (var property in object) {
        var val = object[property];
        // do stuff
        console.log("property: " + property + ", val: " + val);
    }
});

JSFiddle: http://jsfiddle.net/TrueBlueAussie/5hkr8k2x/

score 1 · Answer 3 · answered Aug 08 '14 at 13:14

1

You could look at using the jQuery.each function:

$.each(db, function(index, record) {
    $.each(record, function(key, value) {
        console.log(key + ': ' + value);
    });
});

answered Aug 08 '14 at 13:14

Andy

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5
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Retrieving labels from JSON objects in javascript

3 Answers3

e.g.

JSFiddle: http://jsfiddle.net/TrueBlueAussie/5hkr8k2x/