1/* 2 * Copyright (c) 2025 Huawei Device Co., Ltd. 3 * Licensed under the Apache License, Version 2.0 (the "License"); 4 * you may not use this file except in compliance with the License. 5 * You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software 10 * distributed under the License is distributed on an "AS IS" BASIS, 11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 * See the License for the specific language governing permissions and 13 * limitations under the License. 14 */ 15 16// 并发函数返回Promise 17// 并发函数中返回Promise的表现需关注，其中并发同步函数会处理返回该Promise并返回结果，如下例所示。 18// [Start concurrent_taskpool_promise_return] 19import { taskpool } from '@kit.ArkTS'; 20 21@Concurrent 22function testPromise(args1: number, args2: number): Promise<number> { 23 return new Promise<number>((resolve, reject) => { 24 resolve(args1 + args2); 25 }); 26} 27 28@Concurrent 29async function testPromise1(args1: number, args2: number): Promise<number> { 30 return new Promise<number>((resolve, reject) => { 31 resolve(args1 + args2); 32 }); 33} 34 35@Concurrent 36async function testPromise2(args1: number, args2: number): Promise<number> { 37 return await new Promise<number>((resolve, reject) => { 38 resolve(args1 + args2); 39 }); 40} 41 42@Concurrent 43function testPromise3() { 44 return Promise.resolve(1); 45} 46 47@Concurrent 48async function testPromise4(): Promise<number> { 49 return 1; 50} 51 52@Concurrent 53async function testPromise5(): Promise<string> { 54 return await new Promise((resolve) => { 55 setTimeout(() => { 56 resolve('Promise setTimeout after resolve'); 57 }, 1000) 58 }); 59} 60 61async function testConcurrentFunc() { 62 const task1: taskpool.Task = new taskpool.Task(testPromise, 1, 2); 63 const task2: taskpool.Task = new taskpool.Task(testPromise1, 1, 2); 64 const task3: taskpool.Task = new taskpool.Task(testPromise2, 1, 2); 65 const task4: taskpool.Task = new taskpool.Task(testPromise3); 66 const task5: taskpool.Task = new taskpool.Task(testPromise4); 67 const task6: taskpool.Task = new taskpool.Task(testPromise5); 68 69 taskpool.execute(task1).then((d: object) => { 70 console.info(`task1 res is: ${d}`); // 输出结果：task1 res is: 3 71 }).catch((e: object) => { 72 console.error(`task1 catch e: ${e}`); 73 }) 74 taskpool.execute(task2).then((d: object) => { 75 console.info(`task2 res is: ${d}`); 76 }).catch((e: object) => { 77 console.error(`task2 catch e: ${e}`); // 输出结果：task2 catch e: Error: Can't return Promise in pending state 78 }) 79 taskpool.execute(task3).then((d: object) => { 80 console.info(`task3 res is: ${d}`); // 输出结果：task3 res is: 3 81 }).catch((e: object) => { 82 console.error(`task3 catch e: ${e}`); 83 }) 84 taskpool.execute(task4).then((d: object) => { 85 console.info(`task4 res is: ${d}`); // 输出结果：task4 res is: 1 86 }).catch((e: object) => { 87 console.error(`task4 catch e: ${e}`); 88 }) 89 taskpool.execute(task5).then((d: object) => { 90 console.info(`task5 res is: ${d}`); // 输出结果：task5 res is: 1 91 }).catch((e: object) => { 92 console.error(`task5 catch e: ${e}`); 93 }) 94 taskpool.execute(task6).then((d: object) => { 95 console.info(`task6 res is: ${d}`); // 输出结果：task6 res is: Promise setTimeout after resolve 96 }).catch((e: object) => { 97 console.error(`task6 catch e: ${e}`); 98 }) 99} 100 101@Entry 102@Component 103struct Index { 104 @State message: string = 'Hello World'; 105 106 build() { 107 Row() { 108 Column() { 109 Button(this.message) 110 .fontSize(50) 111 .fontWeight(FontWeight.Bold) 112 .onClick(() => { 113 testConcurrentFunc(); 114 // [StartExclude update_message_on_success] 115 this.message = 'success'; 116 // [EndExclude update_message_on_success] 117 }) 118 } 119 .width('100%') 120 } 121 .height('100%') 122 } 123} 124// [End concurrent_taskpool_promise_return] 125