Question

20

Parsing nested JSON in Nodejs

rated 0 times [ 22] [ 2] / answers: 1 / hits: 26063 / 8 Years ago, tue, august 23, 2016, 12:00:00

I have been trying to parse nested JSON data and below is my code

var string = '{"key1": "value", "key2": "value1", "Key3": {"key31":"value 31"}}';

var obj = JSON.parse(string);

console.log(obj.key1)

console.log(obj[0]);

And this is the output

$ node try.js 

value

undefined

Why I am getting undefined for obj[0]? How to get value in this case, and also for nested key key31?

Update
Now with the help from @SergeyK and others, I have modified my above code as follows

var string = '{"key1": "value1", "key2": "value2", "key3": {"key31":"value 31"}}';



var obj = JSON.parse(string);

var array = Object.keys(obj)



for (var i = 0; i < array.length; i++) {

    console.log(array[i], obj[array[i]]);

}

And the output is as follows

$ node try.js 

key1 value1

key2 value2

key3 { key31: 'value 31' }

But for {"key31":"value 31"} how would I access key key31 and get its value value 31?

Answers

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ammonjesseg

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1 Year ago

answered 8 Years ago longd · Accepted Answer

You just can't access named object property by index. You can use obj[Object.keys(obj)[0]]

Edit:

As @smarx explained in the comments, this answer is not suitable for direct access to the specific property by index due to Object.keys is unordered, so it is only for cases, when you need to loop keys/values of object.

Example:

var string = '{key1: value, key2: value1, Key3: {key31:value 31}}';

var obj = JSON.parse(string);

var keysArray = Object.keys(obj);

for (var i = 0; i < keysArray.length; i++) {

   var key = keysArray[i]; // here is name of object property

   var value = obj[key]; // here get value by name as it expected with objects

   console.log(key, value);

}

// output:

// key1 value

// key2 value1

// Key3 { key31: 'value 31' }