如何在golang中按值获取枚举变量名？

Question

我用enum来定义id和text值的关系，但是我用id作为enum值，因为我不能用id作为变量名type Gender uint8type MemberType uint8const (    Male Gender = 2    Female Gender = 5    Standard MemberType = 2    VIP MemberType = 5)现在我从 Gender 表和 MemberType 表中选择了 id 5，如何使用它来获取 Gender 的文本“Female”和 MemberType 的文本“VIP”？

Answer 1

如果您尝试获取字符串“Female”和“VIP”

var genders = map[uint8]string{

    2: "Male",

    5: "Female",

}

var memberTypes = map[uint8]string{

    2: "Standard",

    5: "VIP",

}

或者：

var genders = map[Gender]string{

    Male: "Male",

    Female: "Female",

}

var memberTypes = map[MemberType]string{

    Standard: "Standard",

    VIP: "VIP",

}

然后你会有类似的东西

 id := 5

 fmt.Println(genders[id]) // "Female"

 fmt.Println(memberTypes[id]) // "VIP"

 // or...

 fmt.Println(genders[Gender(id)]) // "Female"

 fmt.Println(memberTypes[MemberType(id)]) // "VIP"

Answer 2

根据godoc。这个工作有一个生成器，叫做stringer，在golang.org/x/tools/cmd/stringer

使用stringer，您可以这样做。

/*enum.go*/

//go:generate stringer -type=Pill

type Pill int

const (

    Placebo Pill = iota

    Aspirin

    Ibuprofen

    Paracetamol

    Acetaminophen = Paracetamol

)

保存enum.go，然后运行go generate。stringer 将为您完成所有工作。

in the same directory will create the file pill_string.go, in package 

painkiller, containing a definition of

func (Pill) String() string

That method will translate the value of a Pill constant to the string

representation of the respective constant name, so that the call

fmt.Print(painkiller.Aspirin)

will print the string "Aspirin".

Answer 3

将选定的 id 转换为Gender类型。例子：

selectedID := 5

selectedGender := Gender(selectedID)

fmt.Println(selectedGender == Female) // true

anotherSelectedID := 5

selectedMemberType := MemberType(anotherSelectedID)

fmt.Println(selectedMemberType == VIP) // true

游乐场： https: //play.golang.org/p/pfmJ0kg7cO3