如何在 Flutter Dart 中同时使用 .sort 和 .toSet 方法

Question

List colour= ["peach","red","yellow","green","black"];

//How to use both.sort and.toSet methods together in Flutter Dart.

Answer 1

Sort method return type void so you can not use.toSet Method together. But after applying sort you can use.toSet method it works as you expected

Try this

List colour= ["peach","red","yellow","green","black"]; 
colour.sort((a, b) => a.length.compareTo(b.length));   
colour.toSet().toList();

Answer 2

Try this extension:

extension SortEX on List {
  List sortAndSet() {
    sort();
    return toSet().toList();
  }
}

the result you get:

//[black, green, peach, red, yellow]

Answer 3

Sort the List first, then toSet()

List colour= ["peach","red","yellow","green","black", "black"];

colour.sort();
var res = colour.toSet();
print(res); //{black, green, peach, red, yellow}