浅析go中Ticker,Timer和Tick的用法与区别

func main() {
    t1 := time.NewTicker(3 * time.Second)
    defer t1.Stop()
    for {
       select {
       case <-t1.C:
          fmt.Printf("%s\n", time.Now())
       }
    }
}

func main() {
    t1 := time.NewTimer(3 * time.Second)
    defer t1.Stop()
    for {
       t1.Reset(3 * time.Second)
       select {
       case <-t1.C:
          fmt.Printf("%s\n", time.Now())
       }
    }
}

func main() {
    t1 := time.NewTimer(3 * time.Second)
    defer t1.Stop()

    ctx, cancel := mockRPC()
    select {
    case <-ctx.Done():
       fmt.Printf("rpc end\n")
       break
    case <-t1.C:
       // t1时间到了，rpc还没执行完，则执行cancel()并退出
       fmt.Printf("%s\n", time.Now())
       cancel()
    }
}

// mockRPC. 异步执行5s钟，如果已经结束了则停止执行
func mockRPC() (context.Context, context.CancelFunc) {
    ctx, cancel := context.WithCancel(context.Background())
    go func() {
       for i := 0; i < 5; i++ {
          select {
          case <-ctx.Done():
             break
          default:
             fmt.Printf("%d\n", i)
             time.Sleep(time.Second)
          }
       }
    }()

    return ctx, cancel
}

func Tick(d Duration) <-chan Time {
    if d <= 0 {
       return nil
    }
    return NewTicker(d).C
}

func main() {
    t1 := time.Tick(3 * time.Second)
    for {
       select {
       case <-t1:
          fmt.Printf("%s\n", time.Now())
       }
    }
}