next ArkUI parses using arkts json

JSON Parsing and Generation with ArkTS

Module Introduction

This module facilitates the conversion of JSON text to corresponding ArkTS objects or values and vice - versa.

Importing the Module

import { JSON } from '@kit.ArkTS';

JSON Parsing

Using JSON.parse

parse(text: string, reviver?: Transformer, options?: ParseOptions): Object | null

This function parses a JSON string to generate the corresponding ArkTS object or null.

• ** Supported from API version 12 in meta - services.
• System Capability: SystemCapability.Utils.Lang

Parameters:

Parameter Name	Type	Required	Description
text	string	Yes	A valid JSON string.
reviver	Transformer	No	A transformation function that can modify the original values generated by parsing. Default: undefined.
options	ParseOptions	No	Configuration for parsing that can control the generated type. Default: undefined.

Return Value:

Type	Description
Object	null

Error Codes:

Error Code ID	Error Message
401	Parameter error. Possible causes: 1. Mandatory parameters are missing; 2. Incorrect parameter types; 3. Parameter verification failed.

Example:

let jsonText = '{"name": "John", "age": 30, "city": "ChongQing"}';
let obj = JSON.parse(jsonText);
console.info("getname --- > " + (obj as object)?.["name"]);
console.info("getage --- > " + (obj as object)?.["age"]);
console.info("getcity --- > " + (obj as object)?.["city"]);

In this example, we use the JSON.parse method to obtain the obj object and then retrieve values using (obj as object)?.["name"].

Example with interface:

interface Person {
  name: string;
  age: number;
  city: string;
}
let jsonText = '{"name": "John", "age": 30, "city": "ChongQing"}';
let person: Person = JSON.parse(jsonText) as Person;
console.info("personinterface getpersonname --- > " + person.name);
console.info("personinterface getpersonage --- > " + person.age);
console.info("personinterface getpersoncity --- > " + person.city);

Example with class:

class Persontest {
  name: string = '';
  age: number = 0;
  city: string = '';
}
let jsonText = '{"name": "John", "age": 30, "city": "ChongQing"}';
let persontest: Persontest = JSON.parse(jsonText.toString()) as Persontest;
console.info("personclass getpersontest --- > " + persontest.name);
console.info("personclass getpersontest --- > " + persontest.age);
console.info("personclass getpersontest --- > " + persontest.city);

Converting Objects or Arrays to JSON - JSON.stringify

This method converts an ArkTS object or array to a JSON string, supporting linear container conversion. Non - linear containers are not supported.

• ** Supported from API version 12 in meta - services.
• System Capability: SystemCapability.Utils.Lang

Parameters:

Parameter Name	Type	Required	Description
value	Object	Yes	The ArkTS object or array to be converted. Linear containers are supported for conversion, while non - linear containers are not.
replacer	Transformer	No	During serialization, each property of the value being serialized is transformed and processed by this function. Default: undefined.
space	string	number	No

Return Value:

Type	Description
string	The converted JSON string.

Example:

interface Person {
  name: string;
  age: number;
  city: string;
}
let testobj = { "name": "John", "age": 30, "city": "ChongQing" } as Person;
let str1 = JSON.stringify(testobj);
console.info("jsonstringify getstr1 --- > " + str1);