使用sync.WaitGroup等待goroutine完成。关闭通道以使通道上的循环读取退出。
package mainimport ( "fmt" "sync")type workerChannel chan uint64const num_workers = 5func main() { results := make(chan string) workCh := make(workerChannel) // Start workers var wg sync.WaitGroup wg.Add(num_workers) for i := 0; i < num_workers; i++ { go func(num int) { defer wg.Done() // Loop processing work until workCh is closed for w := range workCh { results <- fmt.Sprintf("worker %d, task %d", num, w) } }(i) } // Close result channel when workers are done go func() { wg.Wait() close(results) }() // Send work to be done go func() { for i := 0; i < 21; i++ { workCh <- uint64(i) } // Closing the channel causes workers to break out of loop close(workCh) }() // Process results. Loop exits when result channel is closed. for r := range results { fmt.Println(r) }}https://play.golang.org/p/ZifpzsP6fNv
