【TypeScript】解析json字符串

TypeScript解析JSON字符串

简单的JSON字符串解析

1. 解析如下的JSON字符串数组

     let response = '{"id":"1", "name":"Franc"}';

2. 定义与待解析的JSON对象一一对应的接口，如{“id”:“1”, “name”:“Franc”}

interface Employee {
      id: string
      name: string
    }

3. 通过JSON.parse将字符串转化为JSON对象

    let responseObject: Employee = JSON.parse(response);
    console.info('===responseObject'+responseObject[0].id)
    console.info('===responseObject'+responseObject[1].name)

其他的格式类似

    let response = '[{"id":"1", "name":"Franc"}, {"id":"2","name":"Tom"}]';
    interface Employee {
      id: string
      name: string
    }
     let responseObject: Employee = JSON.parse(response);
    console.info('===responseObject'+responseObject[0].id)
    console.info('===responseObject'+responseObject[1].name)

存在层层嵌套的JSON字符串解析

4. 比如我们需要解析的JSON字符串是如下格式

let jsonObjects = "{
 "device_id": "63e48c9a1eaf704179aa270a_fly20230209",
 "shadow": [
  {
   "service_id": "Agriculture",
   "desired": {
    "properties": null,
    "event_time": null
   },
   "reported": {
    "properties": {
     "temperature": 23,
     "humidity": 30,
     "luminance": 434,
     "lightStatus": "OFF",
     "motorStatus": "OFF"
    },
    "event_time": "20230216T102043Z"
   },
   "version": 4111
  }
 ]
}"

2. 借助工具，自动生成相应的接口
   比如：在线JSON转typescript工具：
   生成的接口如下：

export interface Desired {
	properties?: any;
	event_time?: any;
}

export interface Property {
	temperature: number;
	humidity: number;
	luminance: number;
	lightStatus: string;
	motorStatus: string;
}

export interface Reported {
	properties: Property;
	event_time: string;
}

export interface Shadow {
	service_id: string;
	desired: Desired;
	reported: Reported;
	version: number;
}

export interface RootObject {
	device_id: string;
	shadow: Shadow[];
}

3. 定义一个根接口类型的变量，然后将需要解析的变量通过“JSON.parse（）”将字符串转化为JSON对象即可

let jsonObject: RootObject = JSON.parse(data.result);

但是有时候，我们从网络上请求回来的数据时本身就是JSON格式时，如果通过直接赋值无法解决可以尝试如下方法

let jsonObject: RootObject = JSON.parse(data.result as string);
//或者可以试一试
let jsonObject: RootObject = JSON.parse(JSON.stringify(data.result));