class Site(val map: Map<String, Any?>) { val name: String by map val url: String by map } fun main(args: Array<String>) { // 构造函数接受一个映射参数 val site = Site(mapOf( "name" to "W3xue教程", "url" to "www.w3xue.com" )) // 读取映射值 println(site.name) println(site.url) }