Kotlin  filterIsInstance filterNotNull forEach

 

fun main(args: Array<String>) {val i1 = MyItem(1, 1)val i2: MyItem? = nullval i3: Int = 3val i4 = "4"val i5 = nullval i6 = MyItem(6, 6)val list = mutableListOf<Any?>(i1, i2, i3, i4, i5, i6)list.filterIsInstance(MyItem::class.java).forEach {println(it)}println("---")list.filterNotNull().forEach {println(it)}
}class MyItem {private var id = -1private var pos = -1constructor(id: Int, pos: Int) {this.id = idthis.pos = pos}override fun toString(): String {return "id=${id} pos=${pos}"}
}

 

 

 

 

 

id=1 pos=1
id=6 pos=6
---
id=1 pos=1
3
4
id=6 pos=6

 

 

 

 

Kotlin HashMap entries.filter过滤forEach_kotlin map.entries.foreach-CSDN博客文章浏览阅读997次。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。kotlin协程flow filter map flowOn zip combine（1）_zhangphil的博客-CSDN博客。_kotlin map.entries.foreachhttps://blog.csdn.net/zhangphil/article/details/133990762