JSON summary and its parsing (for Java). __php

first, JSON introduction

JSON (JavaScript Object notation), similar to XML, is a data interchange format, such as Java, which produces a data that wants to be given to JavaScript, and uses JSON in addition to XML;

The advantage of JSON over XML is that it is simple to express;

Official website: http://www.json.org/

JSON is an X in Ajax (that is, it can replace XML); ------from the founder of JSON;

Note: JSON is not a document format, there are no *.json documents, general JSON-formatted documents exist in TXT, and XML can be a standard;

Two, JSON data structure

JSON has two types of data structures:

(1) Map, also known as object; }

(2) array;[...]

That is to say, all JSON objects are represented in these forms;

1.Map

Simply put is the map in Java, name-value pairs of the form given, the name and value between ":" Separated by "," between two map separated by "," the general representation is as follows:

{' Key1 ': ' value1 ', ' key2 ': ' value2 '}

The following is the official website chart:

2.Array

is an array of ordinary meanings, the general form is as follows:

[' arr1 ', ' arr2 ', ' arr3 '];

The following is the official website chart:

The value in the figure can be:

Summary:

(1) There are only two types of JSON data structures;

(2) can be nested representations, such as array can be nested object, etc.;

(3) Remember: object is expressed as {}, array is represented by [];

three, JSON and XML interchange examples

Any XML mentioned above can be converted into a JSON package;

1. Simple XML

XML format:

[HTML] view plain copy <person> <name>xiazdong</name> <age>20</age> </person>

JSON format:

[HTML] view plain copy {' name ': ' Xiazdong ', ' Age ': 20}

2. Complex XML

XML format:

[HTML]   View plain copy <section>       <title> book</title>       <signing>            <author name= "Author-1"/>            <book title= "Book1"  price= "$11"/>       </signing