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

问题

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]"

回答1:

Use alert(JSON.stringify(theObject));

回答2:

theObject.toString()

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

回答3:

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 ) );

回答4:

Use

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

来源：https://stackoverflow.com/questions/16493498/json-stringify-returns-object-object-instead-of-the-contents-of-the-object