1.代碼寫法如下:
fun main(args: Array<String>) {
val list: ArrayList<String>? = arrayListOf<String>("美女", "范冰冰", "柳巖")
val let = list?.let {
it.size
}
}
- 任意對(duì)象都有l(wèi)et擴(kuò)展函數(shù)
- let函數(shù)參數(shù)也是一個(gè)函數(shù)共螺，不帶字面值接收值
- 函數(shù)參數(shù)它的參數(shù)是調(diào)用者本身
- let函數(shù)返回值是它的函數(shù)參數(shù)的返回值
