import 'dart:match';
import 'dart:async';
int getInt(){
print('執(zhí)行g(shù)etInt的函數(shù)');
Random rng = Random();
return rng.nextInt(100);
}
void main(){
//此處調(diào)用的getint函數(shù)是int類型
Future<int> future = Future(getInt);
//驗(yàn)證是否Future<int>的實(shí)例
print(Future(getInt));
}

import 'dart:match';
import 'dart:async';
int getInt() async{
print('執(zhí)行g(shù)etInt的函數(shù)');
Random rng = Random();
return rng.nextInt(100);
}
void main(){
//此處調(diào)用的getint函數(shù)是int類型
Future<int> future = Future(getInt);
//驗(yàn)證是否Future<int>的實(shí)例
print(Future(getInt));
}

import 'dart:match';
import 'dart:async';
int getInt(){
print('執(zhí)行g(shù)etInt的函數(shù)');
Random rng = Random();
return rng.nextInt(100);
}
void main(){
//此處調(diào)用的getint函數(shù)是int類型
Future<int> future = Future(getInt);
future.then((Object onValue){
print('異步調(diào)用成功,值為$onValue');
}).catchError((Object onError){
print('異步調(diào)用失敗,值為$onError');
}).whenCompete((){
print('異步操作完成');
});
}

import 'dart:match';
import 'dart:async';
int getInt(){
print('執(zhí)行g(shù)etInt的函數(shù)');
Random rng = Random();
return rng.nextInt(100);
}
void main() async{
//此處調(diào)用的getint函數(shù)是int類型
Future<int> future = Future(getInt);
try{
//使用await等待異步調(diào)用完成使其等同意同步代碼
	var onvalue = await getInt();
	print('一步操作成功：$onvalue');
}on Excrption catch(onError){
	print('異步捕獲失?。?onError');
}finally{
	print('異步捕獲完成');
}
}

//創(chuàng)建Stream
StreamController<int> controller = StreamController<int>(
	onListen: startTimer,
	onPause: stopTimer,
	onResume: startTimer,
	onCAncel: stoptimer
);
Stream stream = controller.stream;

import 'dart:async';
Stream<int> createStream(Duration interval,int maxCount){
	//定義流控制器
	StreamController<int> controller;
	 //定義定時(shí)器
	Timer timer;
	//計(jì)數(shù)變量
	int counter= 0
	void tick(_){
		counter++;
		controller.add(counter);
		//判斷計(jì)數(shù)變量是否達(dá)到了最大值
		if(counter == maxCount){
		//關(guān)閉計(jì)時(shí)器
		timer.cancel();
		//關(guān)閉Stream并通知監(jiān)聽(tīng)器
		controller.clase();
		}
	}
//啟動(dòng)計(jì)時(shí)器
void startTimer(){
	timer = Timer.periodic(interval,tick);
}
void stopTimer(){
if (timer != null){
timer.cancel();
timer = null;
}
print('結(jié)束執(zhí)行');
}
controller = StreamController<int>(
	onListen: startTimer,
	onPause: stopTimer,
	onResume: startTimer,
	onCAncel: stoptimer
);
return controller.stream;
}
void main() async{
Stream<int> stream = createStream(const Duration(senconds:1),10);
	stream.listen((int value){
	print('來(lái)自createStream的值:$value');
	});
}

Interable<int> getNumbers(int number) sync* (
	print('開(kāi)始執(zhí)行');
	int k=0;
	while(k<number) yield k++;
	print('生成器執(zhí)行結(jié)束');
)
void main (){
print('創(chuàng)建interator');
for (int val in numbers){
print('$val');
}
}

Interable<int> getNumbers(int number) async* (
	print('開(kāi)始執(zhí)行');
	int k=0;
	while(k<number) yield k++;
	print('生成器執(zhí)行結(jié)束');
)
void main (){
print('創(chuàng)建interator');
for (int val in numbers){
print('$val');
}
}

Interable<int> getNumberRecursive(int number) sync* (
	print('開(kāi)始執(zhí)行,輸出number：$number');
	if(numner>0){
		yield* getNumberRecursive(number - 1);
	}
	print('生成器執(zhí)行結(jié)束number:$number');
)
void main (){
print('創(chuàng)建interator');
Interable<int> numbers = getNumberRecursive(3);
for (int val in numbers){
print('$val');
}
}