代碼演示

package main

import "fmt"
import "time"

func main() {
	c1 := make(chan string)
	c2 := make(chan string)
	go func() {
		time.Sleep(time.Second * 1)
		c1 <- "one"
	}()
	go func() {
		time.Sleep(time.Second * 2)
		c2 <- "two"
	}()
	for i := 0; i < 2; i++ {
		select {
		case msg1 := <-c1:
			fmt.Println("received", msg1)
		case msg2 := <-c2:
			fmt.Println("received", msg2)
		}
	}
}

代碼運行結果

received one
received two

代碼解讀

• go語言的通道選擇器(select)可以同時等待多個通道操作

• 以上例子就是利用關鍵字select同時等待創建的兩個通道的值

• 對於select語句而言，它會不斷的檢測通道是否有值傳過來，一旦發現傳過來，立刻獲取並輸出

027_go語言中的通道選擇器