JSON.stringify returns "[object Object]" instead of the contents of the object

Question

Here I'm creating a JavaScript object and converting it to a JSON string, but JSON.stringify returns "[object Object]" in this case, instead of displaying the contents of the object. How can I work around this problem, so that the JSON string actually contains the contents of the object?

var theObject = {name:{firstName:"Mark", lastName:"Bob"}};
alert(JSON.stringify(theObject.toString())); //this alerts "[object Object]"

Alerts don't show objects, only strings, you should be using the console for that. And converting an object to a string does the same, you end up with [object Object], as that is the string representation of an object. — adeneo, May 11 '13 at 03:43
Ever wondered why [object Object] ? Have a look at this answer : http://stackoverflow.com/a/25419538/3001704 — kchetan, Nov 15 '16 at 09:33

score 53 · Accepted Answer · answered May 11 '13 at 03:40

53

Use alert(JSON.stringify(theObject));

answered May 11 '13 at 03:40

Arbel

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how to get name from json string – oxygen May 31 '16 at 12:19
@oxygen Per OP example above, Use: `console.log(JSON.stringify(theObject.name.firstName.toString())); // output: "Mark"` – Chris22 Mar 07 '19 at 02:03

score 6 · Answer 2 · answered May 11 '13 at 03:41

6

theObject.toString()

The .toString() method is culprit. Remove it; and the fiddle shall work: http://jsfiddle.net/XX2sB/1/

answered May 11 '13 at 03:41

hjpotter92

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score 4 · Answer 3 · answered May 11 '13 at 03:52

JSON.stringify returns "[object Object]" in this case

That is because you are calling toString() on the object before serializing it:

JSON.stringify(theObject.toString()) /* <-- here */

Remove the toString() call and it should work fine:

alert( JSON.stringify( theObject ) );

score 1 · Answer 4 · answered May 11 '13 at 03:42

1

Use

var theObject = {name:{firstName:"Mark", lastName:"Bob"}};
alert(JSON.stringify(theObject));

answered May 11 '13 at 03:42

Tamil Selvan C

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JSON.stringify returns "[object Object]" instead of the contents of the object

4 Answers4

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