javascript - Convert JS object to JSON string - Stack Overflow

admin管理员组

文章数量:1125929

If I defined an object in JS with:

var j={"name":"binchen"};

How can I convert the object to JSON? The output string should be:

'{"name":"binchen"}'

If I defined an object in JS with:

var j={"name":"binchen"};

How can I convert the object to JSON? The output string should be:

'{"name":"binchen"}'

• javascript
• json
• string
• object

Share Improve this question Follow edited Oct 16, 2019 at 15:42 Kamil Kiełczewski 92.1k3434 gold badges394394 silver badges370370 bronze badges asked Nov 12, 2010 at 8:20 Bin ChenBin Chen 63.3k5656 gold badges146146 silver badges185185 bronze badges 3

• 77 JSON.stringify() is the method you're looking for. – Gowtham Commented Jun 24, 2016 at 5:33
• 13 There's always that first time when you have to learn it. – Egan Wolf Commented Feb 14, 2018 at 8:28
• JSON.stringify is also a good way to copy an object – Justin Meskan Commented Jul 1, 2020 at 0:06

Add a comment  | 

23 Answers 23

Sorted by: Reset to default 2052

All current browsers have native JSON support built in. So as long as you're not dealing with prehistoric browsers like IE6/7 you can do it just as easily as that:

var j = {
  "name": "binchen"
};
console.log(JSON.stringify(j));

With JSON.stringify() found in json2.js or native in most modern browsers.

JSON.stringify(value, replacer, space)
    value       any JavaScript value, usually an object or array.
    replacer    an optional parameter that determines how object
                values are stringified for objects. It can be a
                function or an array of strings.
    space       an optional parameter that specifies the indentation
                of nested structures. If it is omitted, the text will
                be packed without extra whitespace. If it is a number,
                it will specify the number of spaces to indent at each
                level. If it is a string (such as "\t" or " "),
                it contains the characters used to indent at each level.

Check out updated/better way by Thomas Frank:

• JSON stringify revisited

Update May 17, 2008: Small sanitizer added to the toObject-method. Now toObject() will not eval() the string if it finds any malicious code in it.For even more security: Don't set the includeFunctions flag to true.

Douglas Crockford, father of the JSON concept, wrote one of the first stringifiers for JavaScript. Later Steve Yen at Trim Path wrote a nice improved version which I have used for some time. It's my changes to Steve's version that I'd like to share with you. Basically they stemmed from my wish to make the stringifier:

• handle and restore cyclical references
• include the JavaScript code for functions/methods (as an option)
• exclude object members from Object.prototype if needed.

You can use JSON.stringify() method to convert JSON object to String.

var j={"name":"binchen"};
JSON.stringify(j)

For reverse process, you can use JSON.parse() method to convert JSON String to JSON Object.

JSON.stringify(j, null, 4) would give you beautified JSON in case you need beautification also

The second parameter is replacer. It can be used as Filter where you can filter out certain key values when stringifying. If set to null it will return all key value pairs

In angularJS

angular.toJson(obj, pretty);

obj: Input to be serialized into JSON.

pretty(optional):
If set to true, the JSON output will contain newlines and whitespace. If set to an integer, the JSON output will contain that many spaces per indentation.

(default: 2)

If you're using AngularJS, the 'json' filter should do it:

<span>{{someObject | json}}</span>

JSON.stringify turns a Javascript object into JSON text and stores that JSON text in a string.

The conversion is an Object to String

JSON.parse turns a string of JSON text into a Javascript object.

The conversion is a String to Object

var j={"name":"binchen"};

to make it a JSON String following could be used.

JSON.stringify({"key":"value"});

JSON.stringify({"name":"binchen"});

For more info you can refer to this link below.

https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify

One custom defined for this , until we do strange from stringify method

var j={"name":"binchen","class":"awesome"};
var dq='"';
var json="{";
var last=Object.keys(j).length;
var count=0;
for(x in j)
{
json += dq+x+dq+":"+dq+j[x]+dq;
count++;
if(count<last)
   json +=",";
}
json+="}";
document.write(json);

OUTPUT

{"name":"binchen","class":"awesome"}

LIVE http://jsfiddle.net/mailmerohit5/y78zum6v/

I was having issues with stringify running out of memory and other solutions didnt seem to work (at least I couldn't get them to work) which is when I stumbled on this thread. Thanks to Rohit Kumar I just iterate through my very large JSON object to stop it from crashing

var j = MyObject;
var myObjectStringify = "{\"MyObject\":[";
var last = j.length
var count = 0;
for (x in j) {
    MyObjectStringify += JSON.stringify(j[x]);
    count++;
    if (count < last)
        MyObjectStringify += ",";
}
MyObjectStringify += "]}";

MyObjectStringify would give you your string representaion (just as mentioned other times in this thread) except if you have a large object, this should also work - just make sure you build it to fit your needs - I needed it to have a name than array

Woking... Easy to use

$("form").submit(function(evt){
  evt.preventDefault();
  var formData = $("form").serializeArray(); // Create array of object
  var jsonConvert = JSON.stringify(formData);  // Convert to json
});

Thanks

you can use native stringify function like this

const j={ "name": "binchen" }

/** convert json to string */
const jsonString = JSON.stringify(j)

console.log(jsonString) // {"name":"binchen"}

The existing JSON replacements where too much for me, so I wrote my own function. This seems to work, but I might have missed several edge cases (that don't occur in my project). And will probably not work for any pre-existing objects, only for self-made data.

function simpleJSONstringify (obj) {
    var prop, str, val,
        isArray = obj instanceof Array;

    if (typeof obj !== "object")
        return false;

    str = isArray ? "[" : "{";

    function quote (str) {
        if (typeof str !== "string")
            str = str.toString ();

        // When the actual variable was a number, it was returning a number between quotation marks
        // return str.match(/^\".*\"$/) ? str : '"' + str.replace(/"/g, '\\"') + '"';

        // Now, we are verifing if is a number and, if it is, we remove the quotation marks
        str = str.match (/^\".*\"$/) ? str : '"' + str.replace (/"/g, '\\"') + '"';

        if (isNaN (str.replace (/^["]/, '').replace (/["]$/, '')))
            return str;
        else
            return str.replace (/^["]/, '').replace (/["]$/, '');
    }

    for (prop in obj) {
        if (!isArray) {
            // quote property
            str += quote (prop) + ": ";
        }

        // quote value
        val = obj [prop];
        str += typeof val === "object" ? simpleJSONstringify (val) : quote (val);
        str += ", ";
    }

    // Remove last colon, close bracket
    str = str.substr (0, str.length - 2) + ( isArray ? "]" : "}" );

    return str;
}

Use native function JSON.stringify()

let userJson = {
name : 'Richard'
}
let userJsonString = JSON.stringify(userJson)

if you want to get json properties value in string format use the following way

var i = {"x":1}

var j = JSON.stringify(i.x);

var k = JSON.stringify(i);

console.log(j);

"1"

console.log(k);

'{"x":1}'

For debugging in Node JS you can use util.inspect(). It works better with circular references.

var util = require('util');
var j = {name: "binchen"};
console.log(util.inspect(j));

Just use JSON.stringify to do such conversion - however remember that fields which have undefined value will not be included into json

var j={"name":"binchen", "remember":undefined, "age": null };

var s=JSON.stringify(j);

console.log(s);

The field remember 'disappear' from output json

So in order to convert a js object to JSON String: 

The simple syntax for converting an object to a string is

JSON.stringify(value)

The full syntax is: JSON.stringify(value[, replacer[, space]])

Let’s see some simple examples. Note that the whole string gets double quotes and all the data in the string gets escaped if needed.

JSON.stringify("foo bar"); // ""foo bar""
JSON.stringify(["foo", "bar"]); // "["foo","bar"]"
JSON.stringify({}); // '{}'
JSON.stringify({'foo':true, 'baz':false}); /* " 
{"foo":true,"baz":false}" */



const obj = { "property1":"value1", "property2":"value2"};
const JSON_response = JSON.stringify(obj);
console.log(JSON_response);/*"{ "property1":"value1", 
"property2":"value2"}"*/

The most popular way is below:

var obj = {name: "Martin", age: 30, country: "United States"};   
// Converting JS object to JSON string
var json = JSON.stringify(obj);
console.log(json);

use JSON.stringify(param1, param2, param3);

What is: -

param1 --> value to convert to JSON

param2 --> function to stringify in your own way. Alternatively, it serves as a white list for which objects need to be included in the final JSON.

param3 --> A Number data type which indicates number of whitespaces to add. Max allowed are 10.

convert str => obj

const onePlusStr = '[{"brand":"oneplus"},{"model":"7T"}]';

const onePLusObj = JSON.parse(onePlusStr);

convert obj => str

const onePLusObjToStr = JSON.stringify(onePlusStr);

References of JSON parsing in JS:
JSON.parse() : click
JSON.stringify() : click

You can use JSON.stringify() to do this

Very easy to use method, but don't use it in release (because of possible compatibility problems).

Great for testing on your side.

Object.prototype.toSource()

//Usage:
obj.toSource();

本文标签： javascriptConvert JS object to JSON stringStack Overflow