Kotlin的可变与不可变Map

• mapOf 不可变map
• mutableMapOf可变map

package com.kotlin.flong.base
import java.util.HashMap
/*
 * map的使用
 */
fun main(args : Array<String>){
     mapOf1()
}
 
fun mapOf1(){
    //不可变
    var map1 = mapOf("age" to 29,"userName" to "寅务")
    val mapSet1 = map1.keys
        //循环遍历
    mapSet1.forEach{
        println(it)
    }
    
    val mapSet2 = map1.values;
    //循环遍历
    mapSet2.forEach{
        println(it)
    }
    
    val mapSet3 = map1.entries
    
    //val是关键字故要用·引号
    map1.forEach { key,`val` ->
        //println("key=$key,value=$`val`")
    }
    
    //循环遍历
    for((key,value) in map1){
        println("key=$key,value=$`value`")
    }
    
    //可变
    //var map2 = mutableMapOf();
    //java 的map
    var map3 = HashMap<String,String>()
    
    map3.put("age","23");
    map3.put("userName","寅务");
    
        //循环遍历
    for(m3 in map3){
        println(m3.key + "," + m3.value)
    }
}