I have an Array var cars = [2,3,..] which holds a few integers. I've added a few values to the array, but I now need to send this array to a page via jQuery's .get method. How can I convert it to a JSON object for sending?

12 Answers

Script for backward-compatibility:

And call:

var myJsonString = JSON.stringify(yourArray); 

Note: The JSON object is now part of most modern web browsers (IE 8 & above). See caniuse for full listing. Credit goes to: @Spudley for his comment below

I made it that way:

if I have:

var jsonArg1 = new Object(); jsonArg1.name = 'calc this'; jsonArg1.value = 3.1415; var jsonArg2 = new Object(); jsonArg2.name = 'calc this again'; jsonArg2.value = 2.73; var pluginArrayArg = new Array(); pluginArrayArg.push(jsonArg1); pluginArrayArg.push(jsonArg2); 

to convert pluginArrayArg (which is pure javascript array) into JSON array:

var jsonArray = JSON.parse(JSON.stringify(pluginArrayArg)) 

Wow, seems it got a lot easier nowadays... 3 ways you can do it:

json = { ...array }; json = Object.assign({}, array); json = array.reduce((json, value, key) => { json[key] = value; return json; }, {}); 

One other way could be this:

 var json_arr = {}; json_arr["name1"] = "value1"; json_arr["name2"] = "value2"; json_arr["name3"] = "value3"; var json_string = JSON.stringify(json_arr); 

I decided to use the json2 library and I got an error about “cyclic data structures”.

I got it solved by telling json2 how to convert my complex object. Not only it works now but also I have included only the fields I need. Here is how I did it:

OBJ.prototype.toJSON = function (key) { var returnObj = new Object(); returnObj.devid = this.devid; returnObj.name = this.name; returnObj.speed = this.speed; returnObj.status = this.status; return returnObj; } 

Or try defining the array as an object. (var cars = {};) Then there is no need to convert to json. This might not be practical in your example but worked well for me.

because my array was like below: and I used .push function to create it dynamically

my_array = ["234", "23423"]; 

The only way I converted my array into json is

json = Object.assign({}, my_array); 

Answered in 2022

I think this is the best and cleanest answer.

Using JSON.stringify(), we convert the JavaScript array to Json string. And using JSON.parse(), we convert Json string to a Json object.

var JsonObject, jsArray; // JS array jsArray = ["one", "two", "three"]; // Convert (js array) to (json object) JsonObject = JSON.parse(JSON.stringify(jsArray)); // type console.log(typeof(JsonObject)); // JsonObject console.log(JsonObject);

If you have only 1 object like the one you asked, the following will work.

var x = [{'a':'b'}]; var b= JSON.stringify(x); var c = b.substring(1,b.length-1); JSON.parse(c); 

Shortest

To generate valid json from array of integers use

let json = `[${cars}]` 

for more general arrays use JSON.stringify(cars) (for object with circular references use this)

let cars = [1,2,3]; cars.push(4,5,6); let json = `[${cars}]`; console.log(json); console.log(JSON.parse(json)); // json validation

You can convert an array to JSON using the Object.assign function. The main issue that I hit with that is that Javascript arrays have a zero based integer key, which in turn allows to access the data in the array.

let fruits = ['Apple', 'Banana'] document.write(fruits[0]) 

Returns:

Apple

When you convert the array to JSON, you get

{"0": "Apple", "1: "Banana"} 

JSON objects on the contrary usually contain arbitrary keys, such as:

{ "some_key": "some value", "other_key: "some other value" }

Happily, you can create a list of items, which works pretty much as an array and then use Object.assign as if it was an array, then convert the output to a JSON object

var items = {}; items["some_key"]="some value"; items["other_key"]="some other value"; const jsonString = JSON.stringify(Object.assign({}, items)) const json_obj = JSON.parse(jsonString); 

The advantage of working with item lists is that you don't have to deal with the JSON data as a string or quotes, commas etc... You can instead just manage the item object filling data in or removing it. When you are done you just convert the item variable to a JSON object and do whatever you need to do with it.

With your cars array: var cars = [2,3,..]. You can use for loop like this

 var carArray = new Array(); for(var c in cars) { var jsonObj = new Object(); jsonObj.car_id = cars[c]; carArray.push(jsonObj); }