在F#中,enumerations(也称为enums)是整型类型,其中将标签分配给值的子集。 您可以使用它们代替文字,使代码更具可读性和可维护性。
声明enumerations
声明enumerations的一般语法是type enum-name = | value1 = integer-literal1 | value2 = integer-literal2...
下面的例子演示了如何使用enumerations
例
// Declaration of an enumeration.type Days = | Sun = 0 | Mon = 1 | Tues = 2 | Wed = 3 | Thurs = 4 | Fri = 5 | Sat = 6// Use of an enumeration.let weekend1 : Days = Days.Satlet weekend2 : Days = Days.Sunlet weekDay1 : Days = Days.Monprintfn "Monday: %A" weekDay1printfn "Saturday: %A" weekend1printfn "Sunday: %A" weekend2
当你编译和执行程序,它产生以下输出
Monday: MonSaturday: SatSunday: Sun