Kotlin 枚举类使用举例

enum class Color {
    RED, GREEN, BLUE
}

enum class HttpStatus(val code: Int, val message: String) {
    OK(200, "Success"),
    NOT_FOUND(404, "Resource not found"),
    SERVER_ERROR(500, "Internal server error")
}

interface Printable {
    fun print()
}
enum class LogLevel : Printable {
    DEBUG {
        override fun print() = println("[DEBUG] Detailed info")
    },
    INFO {
        override fun print() = println("[INFO] Operation log")
    },
    ERROR {
        override fun print() = println("[ERROR] Critical issue")
    }
}

val color = Color.RED
println(color.name)    // 输出: RED
println(color.ordinal) // 输出: 0 (位置索引)

enum class ConnectionState {
    DISCONNECTED, CONNECTING, CONNECTED
}
fun handleState(state: ConnectionState) = when(state) {
    DISCONNECTED -> reconnect()
    CONNECTING -> showProgress()
    CONNECTED -> startDataTransfer()
}

enum class ImageFormat(val extension: String) {
    JPEG(".jpg"), PNG(".png"), WEBP(".webp")
}
fun saveImage(format: ImageFormat) {
    val filename = "image${format.extension}"
    // 保存操作
}

enum class Operation {
    ADD { override fun apply(a,b) = a+b },
    MULTIPLY { override fun apply(a,b) = a*b }
}