Go by Example ไธญๆ็: Defer
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Defer ็จไบ็กฎไฟ็จๅบๅจๆง่กๅฎๆๅ๏ผไผ่ฐ็จๆไธชๅฝๆฐ๏ผไธ่ฌๆฏๆง่กๆธ
็ๅทฅไฝใ
Defer ็็จ้่ทๅ
ถไป่ฏญ่จ็ |
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package main |
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import ( "fmt" "os" ) |
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ๅ่ฎพๆไปฌๆณ่ฆๅๅปบไธไธชๆไปถใ็ถๅๅๅ
ฅๆฐๆฎใๆๅๅจ็จๅบ็ปๆๆถๅ
ณ้ญ่ฏฅๆไปถใ
่ฟ้ๅฑ็คบไบๅฆไฝ้่ฟ |
func main() { |
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ๅจ |
f := createFile("/tmp/defer.txt") defer closeFile(f) writeFile(f) } |
func createFile(p string) *os.File { fmt.Println("creating") f, err := os.Create(p) if err != nil { panic(err) } return f } |
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func writeFile(f *os.File) { fmt.Println("writing") fmt.Fprintln(f, "data") |
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}
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ๅ ณ้ญๆไปถๆถ๏ผ่ฟ่ก้่ฏฏๆฃๆฅๆฏ้ๅธธ้่ฆ็๏ผ ๅณไฝฟๅจ defer ๅฝๆฐไธญไนๆฏๅฆๆญคใ |
func closeFile(f *os.File) { fmt.Println("closing") err := f.Close() |
if err != nil { fmt.Fprintf(os.Stderr, "error: %v\n", err) os.Exit(1) } } |
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ๆง่ก็จๅบ๏ผ็กฎ่ฎคๅๅ ฅๆฐๆฎๅ๏ผๆไปถๅทฒๅ ณ้ญใ |
go run defer.go creating writing closing |
ไธไธไธชไพๅญ: Recover