【Azure Developer】使用.Net Core解析JSON的笔记

在C#中解析JSON的一些历史代码记录，分别记录针对各种情况的解析方式。

DLL的引用

using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

需要使用的类型

JArray：对应JSON字符串中的[]数组表示

JArray x = JArray.Parse(jsonresult);

x[0].ToString()

//或在知晓JSON格式的对象时，可直接反序列化。
JsonConvert.DeserializeObject<List<T>>(jsonresult);

JObject：对应JSON字符串中的{"key":"value"}对象键值对

JObject obj = JObject.Parse(jsoncontent);

obj ["Key Name"].ToString()

//或在知晓JSON格式的对象时，可直接反序列化。
JsonConvert.DeserializeObject<T>(jsoncontent);

JToken：针对JSON中的值为["value1","value2","value3"]的情况使用JToekn解析后，可以直接使用jtoken[i]依次获取value

JToken jtvalue= JToken.Parse(jsonstring);

jtvalue[0].ToString()

JSON字符串格式一：

[
    {
        "tree": [
            {
                "id": "b661f9c2-28ee-800a-b621-118a6787a8e6",
                "name": "Automanage Preview",
                "type": "productname",                
                "tree": [
                    {
                        "id": "d2067d69-7bb0-9ee4-cdf8-097211d4229a",
                        "tree": [
                            {
                                "id": "647d2678-3991-b6f2-595c-5215afaaa61a",
                                "type": "category",
                                "typeid": "bcc1837c-6364-a038-6359-afaa3b5144b5",                                
                                "tags": []
                            },
                            {
                                "id": "cf520d66-1d51-3644-2d60-f26a2ce384c3",
                                "name": "Can't create",
                                "type": "category",
                                "typeid": "5414a0bd-ea3d-77f1-2bed-07800e2c7e32",
                                "state": "public",
                                "tags": []
                            },
                            {
                                "id": "8279780f-d659-5819-0598-f9cca054d8df",
                                "name": "Error when ",
                                "type": "category",
                                "typeid": "6c35e082-3d87-83d4-9fa7-d213a2e998b3",
                                "state": "public",
                                "tags": []
                            },

使用JArray来解析JSON字符串到由JSON Object组成的数组，也可以通过Linq语句来过滤。

JArray x = JArray.Parse(result);

var mc21v = x.Children<JObject>().FirstOrDefault(o => o["tree"][0]["name"] != null && o["tree"][0]["name"].ToString() == "filter value");

通过对象中的tree ->name查找JSON字符串中高亮部分，也是第一级Tree节点下子节点的name来过滤。当获取到mc21v 节点对象后，继续根据是否由数组，是否是对象（由key存在）依次递归来获取JSON中所携带的值。

//mc21v
if (mc21v != null && mc21v["tree"] != null && mc21v["tree"][0]["tree"] != null && mc21v["tree"][0]["tree"].Count() > 0)
{
var name = mc21v["tree"][0]["name"].ToString();
var submc21v = mc21v["tree"][0]["tree"];

foreach (var s in submc21v)
 {
 log.LogInformation(name + " / " + s["name"].ToString());
 }
 }

JSON字符串格式二：

{
    "table_parameters": [
        {
            "header_names": [
                "ID",
                "Name",
                "Time",
                ...
            ],
            "table_parameter_result": [
                [
                    "3125649",
                    "test",
                    "2020-10-23T18:35:52.4121265",
                    .....
                ],
                [
                    "123123545",
                    "test again",
                    "2020-10-23T20:27:27.3168876",
                    ...
                ],
                [
                    "120100503",

以上格式为自定义的JSON表格格式，table_parameters节点中包含表头(header_names)和表内容(table_parameter_result)，所以在获取值时候，就需要使用到JArray和JToken。

   JObject details = JObject.Parse(sdresult);

   JToken resultTableObj = details["table_parameters"][0];

   resultTableObj[i].ToString()

附加一：使用Python读取JSON格式得文件内容并输出

import os, uuid
import json

try:
    local_path = "."
    local_file_name = "All My Case.json"
    upload_file_path = os.path.join(local_path, local_file_name)

    with open(upload_file_path, "r") as data:   
        #print(data.read()) 
        y = json.loads(data.read())
        print(len(y))
        for c in y:
            print(c[0]+","+c[8]+","+c[36]+","+c[42])        

except Exception as ex:
    print('Exception:')
    print(ex)

What is JSON?

• JSON stands for JavaScript Object Notation
• JSON is a lightweight data-interchange format
• JSON is "self-describing" and easy to understand
• JSON is language independent *

MORE JSON: https://www.w3schools.com/js/js_json_intro.asp