1console.log(JSON.stringify({ x: 5, y: 6 }));
2// expected output: "{"x":5,"y":6}"
3
4console.log(JSON.stringify([new Number(3), new String('false'), new Boolean(false)]));
5// expected output: "[3,"false",false]"
6
7console.log(JSON.stringify({ x: [10, undefined, function(){}, Symbol('')] }));
8// expected output: "{"x":[10,null,null,null]}"
9
10console.log(JSON.stringify(new Date(2006, 0, 2, 15, 4, 5)));
11// expected output: ""2006-01-02T15:04:05.000Z""

1var obj = {name: "Martin", age: 30, country: "United States"};
2 
3// Converting JS object to JSON string
4var json = JSON.stringify(obj);
5 
6console.log(json);
7// Prints: {"name":"Martin","age":30,"country":"United States"} 
8"https://www.tutorialrepublic.com/faq/how-to-convert-js-object-to-json-string.php"

1var person={"first_name":"Tony","last_name":"Hawk","age":31};
2var personJSONString=JSON.stringify(person); 

1const myObj = {
2  name: 'Skip',
3  age: 2,
4  favoriteFood: 'Steak'
5};
6
7const myObjStr = JSON.stringify(myObj);
8
9console.log(myObjStr);
10// "{"name":"Skip","age":2,"favoriteFood":"Steak"}"
11
12console.log(JSON.parse(myObjStr));
13// Object {name:"Skip",age:2,favoriteFood:"Steak"}

1var jsonPerson = '{"first_name":"billy", "age":23}';
2var personObject = JSON.parse(jsonPerson); //parse json string into JS object

1Use the JavaScript function JSON.parse() to convert text into a JavaScript object:
2var obj = JSON.parse('{ "name":"John", "age":30, "city":"New York"}');