如何通过 kotlin 中的序数值获得枚举成员？

Question

I know I can get the ordinal value of a enum member using the code Color.BLUE.ordinal .

Now I hope to get Color.Green when I know the ordinal value of a enum member, how can I do?

Code

enum class Color{
    RED,BLACK,BLUE,GREEN,WHITE
}



var aOrdinal=Color.BLUE.ordinal //it's 2

val bOrdinal=3  //How can I get Color.Green

Answer 1

Just use values() function which will return the Array of enum values and use ordinal as an index

Example

val bOrdinal=3

val yourColor : Color = Color.values()[bOrdinal]

Answer 2

👷 Safety first:

// Default to null
val color1: Color? = Color.values().getOrNull(bOrdinal)

// Default to a value
val color2: Color = Color.values().getOrElse(bOrdinal) { Color.RED }

Answer 3

You can use Kotlin enumValues<>() to get it

Example

    enum class Color{
    GREEN,YELLOW
}

fun main(str:Array<String>){
    val c  = enumValues<Color>()[1]
   print("Color name is ${c.name} and ordinal is ${c.ordinal}")
}

Prints "Color name is YELLOW and ordinal is 1"