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I have the following Json result:

(Taken from the console)

data
Object {0: Object, 1: Object, 2: Object, 3: Object, 4: Object, 5: Object, 7: Object}

if i in the console do data[0] i get the following result:

Object {id: 125, Module_id: 2, academy_id: 7, Team_id: 5, end: "2014-08-12 00:00:00"…}

However when i do data.length the value is undefined can anyone tell me what is going on?

I have the following Json result:

(Taken from the console)

data
Object {0: Object, 1: Object, 2: Object, 3: Object, 4: Object, 5: Object, 7: Object}

if i in the console do data[0] i get the following result:

Object {id: 125, Module_id: 2, academy_id: 7, Team_id: 5, end: "2014-08-12 00:00:00"…}

However when i do data.length the value is undefined can anyone tell me what is going on?

• javascript
• jquery
• ajax

Share Improve this question Follow asked Aug 14, 2014 at 12:29 Marc RasmussenMarc Rasmussen 20.6k8383 gold badges223223 silver badges384384 bronze badges 4

• 13 data is not an array... it is an object so don't have length property – Arun P Johny Commented Aug 14, 2014 at 12:30
• 1 Change the JSON structure so it is an array of objects. You're trying to get the length of an object which is invalid. – Bobby W Commented Aug 14, 2014 at 12:31
• See this answer: stackoverflow./a/6756305/1232526 – Noy Commented Aug 14, 2014 at 12:32
• Try this instead Object.keys(data).length – Dalorzo Commented Aug 14, 2014 at 12:34

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 6

Use Object.keys

Object.keys(data).length;

DEMO

The Object.keys() method returns an array of a given object's own enumerable properties, in the same order as that provided by a for...in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well).

You structured your json result as an Object not an Array. Do not mix those up! data[0] is the value of the first instance variable of the result object. If you want to structure your json object as an array before sending it to be parsed, then in your php file make sure you encode the object as an array

read.php

<?
    $data = array('a' => 1, 'b' => 2, 'c' => 3);
    print json_encode($data);
?>

This will work as expected:

Object.getOwnPropertyNames(data).length

I have the following Json result:

(Taken from the console)

data
Object {0: Object, 1: Object, 2: Object, 3: Object, 4: Object, 5: Object, 7: Object}

if i in the console do data[0] i get the following result:

Object {id: 125, Module_id: 2, academy_id: 7, Team_id: 5, end: "2014-08-12 00:00:00"…}

However when i do data.length the value is undefined can anyone tell me what is going on?

I have the following Json result:

(Taken from the console)

data
Object {0: Object, 1: Object, 2: Object, 3: Object, 4: Object, 5: Object, 7: Object}

if i in the console do data[0] i get the following result:

Object {id: 125, Module_id: 2, academy_id: 7, Team_id: 5, end: "2014-08-12 00:00:00"…}

However when i do data.length the value is undefined can anyone tell me what is going on?

• javascript
• jquery
• ajax

Share Improve this question Follow asked Aug 14, 2014 at 12:29 Marc RasmussenMarc Rasmussen 20.6k8383 gold badges223223 silver badges384384 bronze badges 4

• 13 data is not an array... it is an object so don't have length property – Arun P Johny Commented Aug 14, 2014 at 12:30
• 1 Change the JSON structure so it is an array of objects. You're trying to get the length of an object which is invalid. – Bobby W Commented Aug 14, 2014 at 12:31
• See this answer: stackoverflow./a/6756305/1232526 – Noy Commented Aug 14, 2014 at 12:32
• Try this instead Object.keys(data).length – Dalorzo Commented Aug 14, 2014 at 12:34

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 6

Use Object.keys

Object.keys(data).length;

DEMO

The Object.keys() method returns an array of a given object's own enumerable properties, in the same order as that provided by a for...in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well).

You structured your json result as an Object not an Array. Do not mix those up! data[0] is the value of the first instance variable of the result object. If you want to structure your json object as an array before sending it to be parsed, then in your php file make sure you encode the object as an array

read.php

<?
    $data = array('a' => 1, 'b' => 2, 'c' => 3);
    print json_encode($data);
?>

This will work as expected:

Object.getOwnPropertyNames(data).length

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