ios - 为什么我对 array.sorted( 的实现是 : ) in Swift returning a strange order?

Question

我有一个自定义类:

class MyClass: MySuperClass
{
    var myNumber: Int

    required init ( id: Int, myNumber: Int )
    {
        self.myNumber = myNumber
        super.init( id: id )
    }

    required init ( id: Int )
    { 
        fatalError( "init() has not been implemented" ) 
    }
}

我创建了一个长度为 20 的对象数组:

var myNumbers: [ MyClass ] = []

我遍历数组，打印出 myNumber 的值:

0
1
1221
0
0
18394
0
0
0
0
0
1222
6
0
110
0
0
24
71
2

然后我对它们进行排序:

myNumbers.sorted( by: { $0.myNumber < $1.myNumber } )

然后我第二次遍历数组，打印出 myNumber 的值:

0
0
0
0
0
0
0
0
0
0
0
2
1
6
24
71
110
1222
1221
18394

如您所见，它有点对它们进行了排序，但不是很令人满意。

请问我做错了什么？提前谢谢你。

Answer 1

你想要.sortInPlace我相信..

myNumbers.sortInPlace( by: { $0.myNumber < $1.myNumber } )

/// Sort `self` in-place according to `isOrderedBefore`.
///
/// The sorting algorithm is not stable (can change the relative order of
/// elements for which `isOrderedBefore` does not establish an order).
///
/// - Requires: `isOrderedBefore` is a
///   [strict weak ordering](http://en.wikipedia.org/wiki/Strict_weak_order#Strict_weak_orderings)
///   over the elements in `self`.