Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Selected Reading
JSON. stringify( ) function in JavaScript
The JSON.stringify() method converts a JavaScript object or value to a JSON string. This is the reverse of JSON.parse() which converts JSON strings back to JavaScript objects.
Syntax
JSON.stringify(value, replacer, space)
Parameters
value: The JavaScript value to convert to JSON string (required)
replacer: Function or array to transform values (optional)
space: Number of spaces or string for indentation (optional)
Basic Example
<html>
<head>
<title>JSON.stringify Example</title>
</head>
<body>
<script type="text/javascript">
var obj = {Tutorial: "JavaScript", Version: "ES6", Active: true};
var jsonString = JSON.stringify(obj);
document.write("Object: " + JSON.stringify(obj) + "<br>");
document.write("Array: " + JSON.stringify([1, 2, 3]) + "<br>");
document.write("String: " + JSON.stringify("Hello"));
</script>
</body>
</html>
Output
Object: {"Tutorial":"JavaScript","Version":"ES6","Active":true}
Array: [1,2,3]
String: "Hello"
Using Replacer Function
<html>
<head>
<title>JSON.stringify with Replacer</title>
</head>
<body>
<script type="text/javascript">
var data = {name: "John", age: 30, password: "secret123"};
// Hide password field
var result = JSON.stringify(data, function(key, value) {
if (key === "password") return undefined;
return value;
});
document.write(result);
</script>
</body>
</html>
Output
{"name":"John","age":30}
Pretty Formatting with Space Parameter
<html>
<head>
<title>JSON.stringify Formatted</title>
</head>
<body>
<script type="text/javascript">
var obj = {name: "Alice", skills: ["HTML", "CSS", "JS"]};
var formatted = JSON.stringify(obj, null, 2);
document.write("<pre>" + formatted + "</pre>");
</script>
</body>
</html>
Output
{
"name": "Alice",
"skills": [
"HTML",
"CSS",
"JS"
]
}
Key Points
-
undefined, functions, and symbols are omitted from objects -
Dateobjects are converted to ISO strings -
NaNandInfinitybecomenull - Only enumerable properties are included
Conclusion
JSON.stringify() is essential for converting JavaScript objects to JSON strings for data storage or transmission. Use the optional parameters for custom formatting and filtering.
Updated on: 2026-03-15T23:18:59+05:30
319 Views
Advertisements