Go 中的 select 语句函数

Go编程语言中 select 语句的语法如下-

select {
   case communication clause  :
      statement(s);      
   case communication clause  :
      statement(s); 
   /* 你可以有任意数量的case语句 */
   default : /* 可选 */
      statement(s);
}

select - 示例

package main

import "fmt"

func main() {
   var c1, c2, c3 chan int
   var i1, i2 int
   select {
      case i1=<-c1:
         fmt.Printf("received ", i1, " from c1\n")
      case c2 <- i2:
         fmt.Printf("sent ", i2, " to c2\n")
      case i3, ok := (<-c3):  //等同于：i3, ok := <-c3
         if ok {
            fmt.Printf("received ", i3, " from c3\n")
         } else {
            fmt.Printf("c3 is closed\n")
         }
      default:
         fmt.Printf("no communication\n")
   }    
}   

编译并执行上述代码后，将产生以下输出-

无涯教程网

no communication