简介Go语言中的select语句的用法

select {
    case communication clause  :
       statement(s);     
    case communication clause  :
       statement(s);
    /* you can have any number of case statements */
    default : /* Optional */
       statement(s);
}

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):  // same as: 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")
   }   
}

no communication