php小編子墨為您介紹如何在錯誤時停止從通道讀取。在進行通道讀取操作時，有時會遇到錯誤情況，例如通道已關閉或讀取逾時。為了確保程式的穩定性和可靠性，我們需要在這些錯誤發生時及時停止讀取操作。可以透過設定錯誤處理程序或使用異常處理機制來實現，在捕獲到錯誤後，立即終止讀取操作，並進行相應的錯誤處理。這樣可以有效避免程式因錯誤而導致的異常情況，提高程式碼的健全性和可維護性。
一旦遇到錯誤，我想停止從通道讀取。我認為我需要使用 errroup.WithContext() 但我無法完全理解如何整合它。
這是輸出：
Thread 2: STARTED Thread 1: STARTED Thread 0: STARTED Thread 2: GOT=0 Thread 1: GOT=1 Thread 0: GOT=2 Thread 0: FAILED Thread 1: GOT=3 Thread 2: GOT=4 Thread 2: GOT=5 Thread 1: GOT=6 Thread 1: GOT=7 Thread 2: GOT=8 panic: Thread 0: FAILED
package main
import (
"fmt"
"time"
"golang.org/x/sync/errgroup"
)
func main() {
const threads = 3
ch := make(chan int, threads)
eg := errgroup.Group{}
for i := 0; i < threads; i++ {
i := i
eg.Go(func() error {
fmt.Printf("Thread %d: STARTED\n", i)
for n := range ch {
fmt.Printf("Thread %d: GOT=%d\n", i, n)
time.Sleep(time.Duration(1) * time.Second)
// Simulate failed thread
if n == 2 {
fmt.Printf("Thread %d: FAILED\n", i)
return fmt.Errorf("Thread %d: FAILED", i)
}
}
return nil
})
}
for i := 0; i < 9; i++ {
ch <- i
}
close(ch)
if err := eg.Wait(); err != nil {
panic(err)
}
}............................................... .... ......................................
errroup.WithContext()# 可能是最好的方法（如你所猜測的）。 這個答案值得一讀；它提供了全面的解釋（我不會嘗試複製！）。
但是，由於這可能很難理解，這裡是使用您的程式碼的一種解決方案（playground ）：
package main
import (
"context"
"fmt"
"time"
"golang.org/x/sync/errgroup"
)
func main() {
const threads = 3
ch := make(chan int, threads)
eg, ctx := errgroup.WithContext(context.Background())
for i := 0; i < threads; i++ {
i := i
eg.Go(func() error {
fmt.Printf("Thread %d: STARTED\n", i)
for n := range ch {
fmt.Printf("Thread %d: GOT=%d\n", i, n)
time.Sleep(time.Duration(1) * time.Second)
// Simulate failed thread
if n == 2 {
fmt.Printf("Thread %d: FAILED\n", i)
return fmt.Errorf("Thread %d: FAILED", i)
}
// For the purpose of this example we will just check the context after
// doing the work.
if ctx.Err() != nil {
fmt.Printf("Thread %d: Quiting due to context\n", i)
return fmt.Errorf("Thread %d: Context cancelled: ", i)
}
}
return nil
})
}
// We want to stop sending new work if there is a failure (otherwise `ch <- i` will block permanently);
sendLoop:
for i := 0; i < 9; i++ {
select {
case ch <- i:
case <-ctx.Done():
fmt.Printf("stopped\n")
break sendLoop // Just exit the loop if something goes wrong (you may want to do something else here)
}
}
close(ch) // Note: Important that this happens even if there is an error (otherwise `for n := range ch` may block, leaking goroutines)
fmt.Printf("all sent\n")
if err := eg.Wait(); err != nil {
panic(err)
}
}以上是如何在錯誤時停止從通道讀取？的詳細內容。更多資訊請關注PHP中文網其他相關文章！
