1. What is JSON?

JSON is only a data format (it is not a new data type) var obj = {name: “China”, age: 5000}; //- > Ordinary Format Object var jsonObj = {“name”: “China”, “age”: 5000}; //- > JSON format object (as long as the attribute name of ordinary object is wrapped with "" (not ”’), this format is our JSON format object) var data = [ {name: "", age: ""}, {name: "", age: ""} ];//- > Ordinary 2-dimensional array

var jsonData = [ {“name”: "", “age”: ""}, {“name”: "", “age”: ""} ];//- > Data in JSON format

2. In the window browser object, we are provided with one method to manipulate JSON format data

- > window.JSON - > stringify: Converts an JSON/normal object to an JSON string - > parse: Converts an JSON-formatted string to an JSON-formatted object

var data = [ {name: “Li 4”, age: 48}, {name: “Zhang 3”, age: 84} ];

var str = JSON.stringify(data);//- > ’[{“name”: “Li 4”, “age”: 48}, {“name”: “Zhang 3”, “age”: 84}]’ console.log(JSON.parse(str));

3. On compatibility

There is no JSON attribute under window in IE6 and IE7 console.log(window.JSON); - > The output result under IE6 ~ 7 is undefined

How to convert an JSON format string to an JSON format object in case of incompatibility? - > Use eval, but remember that it is best to manually add parentheses to the left and right sides of the string var str = ’[{“name”: “Li 4”, “age”: 48}, {“name”: “Zhang 3”, “age”: 84}]’; var data = eval(”(” + str + ”)”);//- > If compatible, we use JSON. parse (str) console.dir(data);