24.Dart中await和async的并行执行顺序

import 'dart:io';

main(List<String> args) {

  print('star');

  getNetWorktest1();

  getNetWorktest1();

  getNetWorktest1();

  getNetWorktest1();

  print('end');

}

// Future<String> getNetworkData1(String arg){

//    return Future(() {

//      sleep(Duration(seconds: 5));

//      return "KSJ耗时操作测试 + $arg";

//    }

//  );

// }

getNetWorktest1() async{

  var res1 = await getNetWorktest2('KSJ + 1核');

  print(res1);

  var res2 = await getNetWorktest2('KSJ + 2核');

  print(res2);

  var res3 = await getNetWorktest2('KSJ + 3核');

  print(res3);

  var res4 = await getNetWorktest2('KSJ + 4核');

  print(res4);

}

Future<String> getNetWorktest2(String string){

  return Future(() {

      sleep(Duration(seconds: 1));

      return "KSJ耗时操作测试：$string + ${DateTime.now()}";

  }

  );

}

// 业务代码里面一般用then、封装的方法一般用awit和async

// 同时创建多个Future是同步进行操作、但是内部处理进行了分发。分发有需，返回结果无序

// Dart就是单线程加循环——但是Flutter肯定是多线程的，注意范围

⚠️：非常规逻辑执行顺序——所有事件第一步执行完再执行所有事件的第二步依次进行

star

end

KSJ耗时操作测试：KSJ + 1核 + 2020-06-07 09:08:23.077671

KSJ耗时操作测试：KSJ + 1核 + 2020-06-07 09:08:24.102546

KSJ耗时操作测试：KSJ + 1核 + 2020-06-07 09:08:25.103046

KSJ耗时操作测试：KSJ + 1核 + 2020-06-07 09:08:26.107350

KSJ耗时操作测试：KSJ + 2核 + 2020-06-07 09:08:27.109310

KSJ耗时操作测试：KSJ + 2核 + 2020-06-07 09:08:28.112557

KSJ耗时操作测试：KSJ + 2核 + 2020-06-07 09:08:29.116323

KSJ耗时操作测试：KSJ + 2核 + 2020-06-07 09:08:30.118994

KSJ耗时操作测试：KSJ + 3核 + 2020-06-07 09:08:31.122430

KSJ耗时操作测试：KSJ + 3核 + 2020-06-07 09:08:32.127697

KSJ耗时操作测试：KSJ + 3核 + 2020-06-07 09:08:33.130581

KSJ耗时操作测试：KSJ + 3核 + 2020-06-07 09:08:34.136342

KSJ耗时操作测试：KSJ + 4核 + 2020-06-07 09:08:35.139277

KSJ耗时操作测试：KSJ + 4核 + 2020-06-07 09:08:36.144755

KSJ耗时操作测试：KSJ + 4核 + 2020-06-07 09:08:37.149125

KSJ耗时操作测试：KSJ + 4核 + 2020-06-07 09:08:38.153450