JavaScript Ajax-5 JSON (JSON overview, using JSON)

First, JSON overview

JSON overview

-Json:javascript Object Notation,javascript, originally a syntax for creating objects in JavaScript

-now JSON has been isolated from JavaScript as a stand-alone string data representation, supported by almost all major languages such as Java, C #, C + +, PHP, OC, etc.

-JSON, as a lightweight text data Interchange format, has been widely used to store and exchange text data in a similar way to XML, but more concise, faster, and easier to parse than XML

JSON syntax rules

-JSON syntax is a subset of JavaScript object notation syntax:

-Data in name/value pairs

-Data separated by commas

-Curly braces to save objects

-square brackets to save the array

-The basic format of JSON data is "name/value" pairs

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Ii. use of JSON

JSON object

-JSON (JavaScript Object Notation) is a lightweight data interchange format

-a JSON string can describe an object. The specific syntax is:

-written in curly braces;

-can contain any number of "name/value" pairs separated by commas

-the "name" must be enclosed in double quotation marks, and the value must be enclosed in double quotation marks if the string is used

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JSON array

-The JSON string can also describe an array, with the specific syntax

-Written in square brackets

-Where multiple values or objects can be included

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Conversion of JSON documents to objects

-Use the Eval () function to parse a JSON text string into a JavaScript object

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Conversion of JSON documents to objects

-You can also use the Json.parse (string) method to parse a JSON string to get a JavaScript object

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-Format JavaScript objects as JSON strings using the Json.stringify (jsobj) method

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Summary: This chapter focuses on JSON (JSON overview, using JSON)

This article from the "Flying Ants" blog, declined to reprint!

JavaScript Ajax-5 JSON (JSON overview, using JSON)