Channels {.en}

通道 {.zh}

::: {.en} Channels are the pipes that connect concurrent goroutines. You can send values into channels from one goroutine and receive those values into another goroutine. :::

::: {.zh}

通道 (Channels) 是连接多个 Go 协程的管道。你可以从一个 Go 协程 将值发送到通道，然后在别的 Go 协程中接收。

:::

  1. package main
  2. import "fmt"
  3. func main() {

::: {.en} Create a new channel with make(chan val-type). Channels are typed by the values they convey. :::

::: {.zh}

使用 make(chan val-type) 创建一个新的通道。通道类型就是他们需要传递值的类型。

:::

  1.     messages := make(chan string)

::: {.en} Send a value into a channel using the channel <- syntax. Here we send "ping" to the messages channel we made above, from a new goroutine. :::

::: {.zh}

使用 channel <- 语法 发送（send） 一个新的值到通道中。这里 我们在一个新的 Go 协程中发送 “ping” 到上面创建的 messages 通道中。

:::

  1.     go func() { messages <- "ping" }()

::: {.en} The <-channel syntax receives a value from the channel. Here we’ll receive the "ping" message we sent above and print it out. :::

::: {.zh}

<-channel语法接收来自通道的值。在这里，我们将收到上面发送的 ping 消息并打印出来。

:::

  1.     msg := <-messages
  2.     fmt.Println(msg)
  3. }

::: {.en} When we run the program the "ping" message is successfully passed from one goroutine to another via our channel. :::

::: {.zh}

我们运行程序时，通过通道，消息 ping 成功地从一个 Go 协程传到 另一个中。

:::

  1. $ go run channels.go 
  2. ping

::: {.en} By default sends and receives block until both the sender and receiver are ready. This property allowed us to wait at the end of our program for the "ping" message without having to use any other synchronization. :::

::: {.zh}

默认情况下，发送和接收是阻塞的，直到发送方和接收方都准备就绪。这个特性允许我们在程序结束时等待 ping 消息，而不必使用任何其他同步操作。

:::