The format of the json structure is a collection of several key/value (key, value) pairs. This collection can be understood as a dictionary (Dictionary), and each key/value pair can be understood as an object (Object). The key in a key/value pair is generally a string, and the value can be a basic type such as string, double, or int. It can also be a nested key/value pair, or it can be an array or the data in the array. The type can be a basic type, or a key/value pair. It can be seen that key/value is nothing originally, but it will be confusing if it is nested too much. Let's give a specific example to illustrate. Note: This code is only used as an example and will not run correctly.
var testJson = { "Name" : "奥巴马" , "ByName" : ["小奥","小巴","小马"], "Education" : { "GradeSchool" : "华盛顿第一小学", "MiddleSchool" : ["华盛顿第一初中" , "华盛顿第一高中"], "University" : { "Name" : "哈佛大学", "Specialty" : ["软件工程","会计"] } } }
The variable testJson is a json object. The testJson object includes three key/value pairs.
The first key/value pair: The key (key) is "Name", and its corresponding value (value) is "Obama", that is, testJson["Name"] == "Obama"
The second key/ Value pair: The key is "ByName", the value is an array, which is a collection of strings. If necessary, the elements in the array can also be key/value pairs.
The third key/value pair: The key is "Education" and the value is a Json object. The json object includes three key/value pairs. This is nesting. . .
Summary: A json object is a collection of several key/value pairs. The key is string and the value can be a basic type, or a nested Json object, or an array (the elements in the array can be of basic type, or json object, you can continue to nest).
Get the name: testJson["Name"]
Get the first alias: testJson["ByName"][0]. The value corresponding to the key "ByName" of testJson is a string array
Get the primary school name: testJson["Education"]["GradeSchool"] , Get the university major: testJson["Education"]["University"][" Specialty"][0]
The following is an example:
Define a string that meets the json format requirements:
string testJson = "{\"Name\" : \"奥巴马\",\"ByName\" : [\"小奥\",\"小巴\",\"小马\"],\"Education\":{\"GradeSchool\" : \"华盛顿第一小学\",\"MiddleSchool\" : [\"华盛顿第一初中\" , \"华盛顿第一高中\"], \"University\" :{ \"Name\" : \"哈佛大学\", \"Specialty\" : [\"软件工程\",\"会计\"]}}}";
Then you need to use the string as a parameter to create a new JsonObject object. Microsoft's own class library System.Json, and then add the namespace using System.Json;
The main code is just one sentence: JsonObject js = JsonObject.Parse(testJson); Use the string testJson as the parameter to create a new JsonObject object. Through monitoring, we can see that the content in js is as expected. You should be able to figure out a lot of things from the picture below
Insert an additional sentence: js["Education"]["University"][ The content of "Specialty"] is {[ "Software Engineering", "Accounting"]},
But the value of js["Education"]["University"]["Specialty"].Contains("Software Engineering") is false. Figure out the reasons yourself
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