如何利用鸿蒙arkts进行json数据和对象互转-使用JSON库_业界新闻

发布时间:2024-07-17 18:48

阅读量:5

1.鸿蒙系统arkts使用JSON库

JSON库中提供json数据和对象互转方式

interface JSON {     /**      * Converts a JavaScript Object Notation (JSON) string into an object.      * @param text A valid JSON string.      * @param reviver A function that transforms the results. This function is called for each member of the object.      * If a member contains nested objects, the nested objects are transformed before the parent object is.      */     parse(text: string, reviver?: (this: any, key: string, value: any) => any): any;     /**      * Converts a JavaScript value to a JavaScript Object Notation (JSON) string.      * @param value A JavaScript value, usually an object or array, to be converted.      * @param replacer A function that transforms the results.      * @param space Adds indentation, white space, and line break characters to the return-value JSON text to make it easier to read.      */     stringify(value: any, replacer?: (this: any, key: string, value: any) => any, space?: string | number): string;     /**      * Converts a JavaScript value to a JavaScript Object Notation (JSON) string.      * @param value A JavaScript value, usually an object or array, to be converted.      * @param replacer An array of strings and numbers that acts as an approved list for selecting the object properties that will be stringified.      * @param space Adds indentation, white space, and line break characters to the return-value JSON text to make it easier to read.      */     stringify(value: any, replacer?: (number | string)[] | null, space?: string | number): string; }

2.示例

2.1.`Json`文件

{     "userInfo":{       "name":"lili",       "age":30,       "address":"北京市",       "account":"ksnowlv"     },     "subscriptions":[       {         "title":"Flutter入门指南",         "subtitle":"从零开始学习Flutter",         "content":"Flutter是一种用于创建跨平台移动应用程序的开源UI工具包。",         "subscriptionId":"sub001",         "likes":100       },       {         "title":"Dart编程语言介绍",         "subtitle":"学习Dart的基本语法和特性",         "content":"Dart是一种由Google开发的面向对象、类似Java和JavaScript的新型编程语言。",         "subscriptionId":"sub002",         "likes":85       }     ]    }

2.2.`Json`转换为类

export class MyUser {     userInfo?: UserInfo     subscriptions?: Subscriptions[] }  export class Subscriptions {     title?: string     subtitle?: string     content?: string     subscriptionId?: string     likes?: number }  export class UserInfo {     name?: string     age?: number     address?: string     account?: string }

2.3.`Json`转换为对象

    @State myUser: MyUser = null      try {         this.myUser = JSON.parse(this.jsonContent);         const userInfo = this.myUser.userInfo;         console.info(`${this.TAG} userInfo Name: ${userInfo.name} Age: ${userInfo.age} Address: ${userInfo.address} Account: ${userInfo.account}`)          const subscriptions = this.myUser.subscriptions;          subscriptions.forEach((subscription, index) => {             console.info(`${this.TAG} Subscription ${index + 1}:`);             console.info(`${this.TAG}  Title: ${subscription.title}`);             console.info(`${this.TAG}  Subtitle: ${subscription.subtitle}`);             console.info(`${this.TAG}  Content: ${subscription.content}`);             console.info(`${this.TAG}  Subscription ID: ${subscription.subscriptionId}`);             console.info(`${this.TAG}  Likes: ${subscription.likes}`);         });     } catch (error) {         console.error(`${this.TAG} json content:${JSON.stringify(error)}}`)     }

2.4.对象转换`Json`

    try {         let json = JSON.stringify(this.myUser)         console.info(`${this.TAG} objectToJson jsonString :${json}}`)     } catch (error) {         console.error(`${this.TAG} json content:${JSON.stringify(error)}}`)     }

3.效果

前端页面显示

日志输出

05-29 11:32:26.418  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage userInfo Name: lili Age: 30 Address: 北京市 Account: ksnowlv 05-29 11:32:26.419  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage Subscription 1: 05-29 11:32:26.419  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Title: Flutter入门指南 05-29 11:32:26.419  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Subtitle: 从零开始学习Flutter 05-29 11:32:26.419  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Content: Flutter是一种用于创建跨平台移动应用程序的开源UI工具包。 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Subscription ID: sub001 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Likes: 100 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage Subscription 2: 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Title: Dart编程语言介绍 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Subtitle: 学习Dart的基本语法和特性 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Content: Dart是一种由Google开发的面向对象、类似Java和JavaScript的新型编程语言。 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Subscription ID: sub002 05-29 11:32:26.420  20966-7914   0FEFE/JsApp                                        com.example.base_demo                          I  NetPage  Likes: 85 05-29 11:32:44.805  20966-7914   0FEFE/JsApp                                        com.exa