update the last element of List

问题

I have a List

val first = List("A","B","C","D")

and I want to create a new list from it but change the last element only:

val newLastVal = "E"
val second = List("A","B","C","E")

can't figure this one out! Thanks in advance

回答1:

you can also use .init or .dropRight(1) to remove last element and then can add new item to list

val second=first.init:+newLastVal //preferable 

OR

val second=first.dropRight(1):+newLastVal

回答2:

you can use .updated(postion,value)

val second=first.updated(first.length-1,newLastVal)

来源：https://stackoverflow.com/questions/24838826/update-the-last-element-of-list