Node js json
JSON (JavaScript Object Notation) is a data storage and communication format based on key-value pair of JavaScript object literals. It is a lightweight text-based open standard designed for human-readable data interchange which is derived from the JavaScript programming language for representing simple data structures and associative arrays, called objects.
In JSON
all property names are surrounded by double quotes.
values are restricted to simple data: no function calls, variables, comments, or computations.
JSON is used for communication between javascript and serverside technologies.
JSON.stringify(value); is used to convert Javascript objects into JSON.
Example Usage:
var obj={"website":"Onlineinterviewquestions"};
JSON.stringify(obj); // '{"website":"Onlineinterviewquestions"}'
JSON supports Objects, Arrays, Primitives (strings, numbers, boolean values (true/false), null) data types.
Object.create creates a new object with the specified prototype object and properties.
$.parseJSON() takes a well-formed JSON string and returns the resulting JavaScript value.
You can create Object by
object literals
Object.create
constructors
A plain, empty object that derives from Object.prototype is the default value of a constructor’s prototype
It is faster and lighter than XML as on the wire data format
XML data is typeless while JSON objects are typed
JSON types: Number, Array, Boolean, String
XML data are all string
Data is readily available as JSON object is in your JavaScript
Fetching values is as simple as reading from an object property in your JavaScript code
JSON: JSON is a simple data format used for communication medium between different systems
JSONP: It is a methodology for using that format with cross-domain ajax requests while not being affected by same origin policy issue.
JSON-RPC: JSON-RPC is a simple remote procedure call protocol similar to XML-RPC although it uses the lightweight JSON format instead of XML.
JSON-RPC-Java is a Java implementation of the JSON-RPC protocol.Below is list of some of its features
Dynamically call server-side Java methods from JavaScript DHTML web applications. No Page reloading.
Asynchronous communications.
Transparently maps Java objects to JavaScript objects.
Lightweight protocol similar to XML-RPC although much faster.
Leverages J2EE security model with session specific exporting of objects.
Supports Internet Explorer, Mozilla, Firefox, Safari, Opera, and Konqueror.
Following data types are natively supported in JSON.
Numbers: Integer, float or Double
String: string of Unicode characters, must be rapped into double quotes “”
Boolean: True or false
Array: ordered list of 0 or more values
Objects : An unordered collection key/ value pairs
Null: An Empty value
JSON.stringify method is used to convert an Javascript Object into JSON.
Syntax:
let json = JSON.stringify(value[, replacer, space])