golang中chan使用

package main

import (
    "fmt"
    "sync"
    "time"
)

var wg sync.WaitGroup

func writeCh(ch chan<- int) {
    for i := 1; i <= 10; i++ {
        ch <- i
        fmt.Println("写入-", i)
        time.Sleep(time.Millisecond * 50)
    }
    close(ch)
    wg.Done()
}

func readCh(ch <-chan int) {
    for val := range ch {
        fmt.Println("读取-", val)
        time.Sleep(time.Millisecond * 100)
    }
    wg.Done()
}

func main() {
    var ch = make(chan int, 10)
    wg.Add(1)
    go writeCh(ch)
    wg.Add(1)
    go readCh(ch)
    wg.Wait()
}

执行结果

写入- 1
读取- 1
写入- 2
写入- 3
读取- 2
写入- 4
读取- 3
写入- 5
写入- 6
读取- 4
写入- 7
写入- 8
读取- 5
写入- 9
读取- 6
写入- 10
读取- 7
读取- 8
读取- 9
读取- 10