fallthrough:Go里面switch默認(rèn)相當(dāng)于每個case最后帶有break,匹配成功后不會自動向下執(zhí)行其他case,而是跳出整個switch, 但是可以使用fallthrough強(qiáng)制執(zhí)行后面的case代碼。
switch { case false: fmt.Println("The integer was = 4") fallthrough case true: fmt.Println("The integer was = 5") fallthrough case false: fmt.Println("The integer was = 6") fallthrough case true: fmt.Println("The integer was = 7") fallthrough case false: fmt.Println("The integer was = 8") default: fmt.Println("default case") }
輸出結(jié)果:
The integer was = 5
The integer was = 6
The integer was = 7
The integer was = 8
問題:是否在switch最后一個分支使用fallthrough???
有錯誤提示,顯示:cannot fallthrough final case in switch
fallthrough不能用在switch的最后一個分支。
上述示例是true、false常量進(jìn)行分支判斷,看如下變量示例。
s := "abcd" switch s[1] { case 'a': fmt.Println("The integer was = 4") fallthrough case 'b': fmt.Println("The integer was = 5") fallthrough case 'c': fmt.Println("The integer was = 6") default: fmt.Println("default case") }
輸出結(jié)果如下:
The integer was = 5
The integer was = 6
更改為:
s := "abcd" switch s[3] { case 'a': fmt.Println("The integer was = 4") fallthrough case 'b': fmt.Println("The integer was = 5") fallthrough case 'c': fmt.Println("The integer was = 6") default: fmt.Println("default case") }
輸出:
default case
switch分支中使用變量進(jìn)行判斷的時,fallthrough正確的分支開始其作用。
補(bǔ)充:【踩坑】golang的fallthrough大坑
加了fallthrough后,會直接運(yùn)行【緊跟的后一個】case或default語句,不論條件是否滿足都會執(zhí)行,后面的條件并不會再判斷了,?
以上為個人經(jīng)驗,希望能給大家一個參考,也希望大家多多支持腳本之家。如有錯誤或未考慮完全的地方,望不吝賜教。
標(biāo)簽:汕頭 吐魯番 梅河口 雞西 欽州 蘭州 重慶 銅川
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