JSON

JavaScript can encode complex programs. But it can also store data in arrays and objects. With JSON we use JavaScript to store data in an efficient format.

To parse JSON, we can use Node.js—the JSON.parse method is built for this purpose. It returns an easy-to-use JavaScript object.

An example

Here is an example of the JSON.parse method on a string that contains an array. Please notice how the quotes of the "text" string are used to avoid a parsing error.

// This is a JSON text string.
var text = '["cat", "bird", "frog"]';

// Use JSON.parse to convert string to array.
var result = JSON.parse(text);

// Print result count.
console.log("COUNT: " + result.length);
// ... Loop over result.
for (var i = 0; i < result.length; i++) {
    console.log("JSON PARSED ITEM: " + result[i]);
}
COUNT: 3
JSON PARSED ITEM: cat
JSON PARSED ITEM: bird
JSON PARSED ITEM: frog

Stringify

With this method we convert an object model into a string. In this example we just use a string array and convert it into a JSON string.

var array = ["cat", "bird", "frog"];

// Use JSON.stringify to get a string.
var result = JSON.stringify(array);
console.log("STRINGIFY: " + result);
STRINGIFY: ["cat","bird","frog"]

JSON is an efficient and well-supported format for data. Node has excellent support for JSON in the JSON.parse method.