Kotlin HashMap entries.filter过滤forEach

Kotlin HashMap entries.filter过滤forEach

fun main(args: Array<String>) {
    val hashMap = HashMap<String, Int>()
    hashMap["a"] = 1
    hashMap["b"] = 2
    hashMap["c"] = 3

    println(hashMap)

    hashMap.entries.filter {
        println("filter ${it.key}-${it.value}")
        it.key == "b" //此处为过滤条件，满足过滤条件为真，才会进入forEach
    }.forEach {
        println("forEach ${it.key}--${it.value}")
    }
}

{a=1, b=2, c=3}

filter a-1

filter b-2

filter c-3

forEach b--2

kotlin协程flow filter map flowOn zip combine（1）_zhangphil的博客-CSDN博客一、flow ,emit,onCompletion,collect。四、map，重组改写数据。八、conflate 合并。九、debounce去重。二、函数作为flow。https://blog.csdn.net/zhangphil/article/details/130084723