Iterate enum values using values() and valueOf in kotlin

Question

You can use values like so:

val genders = Gender.values()

Since Kotlin 1.1 there are also helper methods available:

val genders = enumValues<Gender>()

With the above you can easily iterate over all values:

enumValues<Gender>().forEach { println(it.name) }

To map enum name to enum value use valueOf/enumValueOf like so:

 val male = Gender.valueOf("Male")
 val female = enumValueOf<Gender>("Female")     

You're getting [LGender;@2f0e140b or similar as the output of printing Gender.values() because you're printing the array reference itself, and arrays don't have a nice default toString implementation like lists do.

The easiest way to print all values is to iterate over that array, like this:

Gender.values().forEach { println(it) }

Or if you like method references:

Gender.values().forEach(::println)

You could also use joinToString from the standard library to display all values in a single, formatted string (it even has options for prefix, postfix, separator, etc):

println(Gender.values().joinToString()) // Female, Male

You can add this method to your enum class.

fun getList(): List<String> {
    return values().map {
        it.toString()
    }
}

And call

val genders = Gender.getList()
// gender is now a List of string
// Female, Male

You can do this and get a new array of your enum type Gender

val arr = enumValues<Gender>()

and if you want a list of its, you can use the extension. toList()