javascript - How to read multi-level json - Stack Overflow

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So, I know how to read a "single-level" json array. However, I can't figure out how to index the value I want from a multi-level json array.

I have this JSON data:

{
    "items": [
        {
            "snippet": {
                "title": "YouTube Developers Live: Embedded Web Player Customization"
            }
        }
    ]
}

I would like to access the value of title, however neither of these access the value, but instead return undefined:

console.log(data["items"][0].title);

or:

console.log(data["items"][0]["title"]);

But, this code returns the snippet object:

console.log(data["items"][0]);

The data variable refers to the json data.

How should I go about this?

So, I know how to read a "single-level" json array. However, I can't figure out how to index the value I want from a multi-level json array.

I have this JSON data:

{
    "items": [
        {
            "snippet": {
                "title": "YouTube Developers Live: Embedded Web Player Customization"
            }
        }
    ]
}

I would like to access the value of title, however neither of these access the value, but instead return undefined:

console.log(data["items"][0].title);

or:

console.log(data["items"][0]["title"]);

But, this code returns the snippet object:

console.log(data["items"][0]);

The data variable refers to the json data.

How should I go about this?

• javascript
• json

Share Improve this question Follow edited Feb 3, 2016 at 17:05 Asons 87.3k1212 gold badges117117 silver badges174174 bronze badges asked Feb 3, 2016 at 16:37 user5773800user5773800

Add a ment  | 

2 Answers 2

Sorted by: Reset to default 5

Try this:

data.items[0].snippet.title

Explanation (you can see corresponding object in /* */ ment):

items[0];
/*
{
    'snippet': {
        'title': 'YouTube Developers Live: Embedded Web Player Customization'
    }
}
*/

items[0].snippet;
/*
{
    'title': 'YouTube Developers Live: Embedded Web Player Customization'
}
*/

items[0].snippet.title;
/*
'YouTube Developers Live: Embedded Web Player Customization'
*/

As addition to madox2's answer, here's an explanation:

{
    "items": [
      {
       "snippet": {
          "title": "YouTube Developers Live: Embedded Web Player Customization"
      }
    }
  ]
}

The root is a Object, while items is an array. Objects are surrounded by curly braces, while arrays are surrounded by sqare braces.

In JS, you can access a Object like this:

parent.child

In your case, assuming you the data is assigned to a variable called data, you would access it with the variable name and the object you want to get:

data.items

Array's have keys - if no keys are specified, the keys will be number-based.

So seeing that items is an array without any key specified, you'll have to access the x-th element. x is in your case 0, because it's the first item of the array (Remember, arrays are zero-indexed):

data.items[0]

And here you have a object again, so access it:

data.items[0].snippet.title

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