如何允许我将方法传递给 List.Sort()？
List<Stuff> list = new List<Stuff>();
list.Sort(StuffSortByName);
： StuffSortByName 声明：
private static int StuffSortByName(Stuff x, Stuff y)
{
...
}
令我惊讶的是我的代码编译并且有效。令人惊讶的是 Sort 没有重载采用方法：
所以我很幸运，因为我不想创建一个实现 IComparer 的整个对象，只是为了对东西进行排序。但就我的一生而言，我在编译时无法理解。
现在我想复制这个魔法。我想对 ListView 进行排序。但是您不对列表进行排序，而是通过它的 ListViewItemSorter 属性：
listView1.ListViewItemSorter = [IComparer]
再说一遍，我不想写整个对象，我只想传递本地方法（最好是非静态方法）：
listView1.ListViewItemSorter = SortListView;
private static int SortListView(Object x, Object y)
{
....
}
现在当然不会编译，因为它没有意义。但是早期的语法也不应该编译 - 但它确实可以编译。
所以它给了我希望，我可以在这里拥有同样令人困惑的语法。
在第一种情况下如何允许我传递一个方法作为排序比较器，但在第二种情况下不允许？
List<Stuff> list = new List<Stuff>();
list.Sort(StuffSortByName);
with the StuffSortByName declaration of:
private static int StuffSortByName(Stuff x, Stuff y)
{
...
}
What surprises me is that my code compiles and works. It's surprising that no overload of Sort takes a method:
So i was fortunate, as i didn't want to have to create a whole object, that implements IComparer, just to sort stuff. But for the life of me i don't understand while it compiles.
And now i want to duplicate that magic. i want to sort a ListView. But you don't sort a listivew, you give a listview an IComparer through it's ListViewItemSorter property:
listView1.ListViewItemSorter = [IComparer]
And, again, i don't want to write a whole object, i just want to pass a local method (and ideally a non-static one):
listView1.ListViewItemSorter = SortListView;
private static int SortListView(Object x, Object y)
{
....
}
Now of course this doesn't compile because it makes no sense. But then the earlier syntax shouldn't compile either - but it does.
So it gives me hope that i can have the same confusing syntax here.
How was i allowed to pass a method as a sort comparer in the first case, but not in the second case?
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要回答您的第一个问题，可以传递方法名称的原因是因为
Comparison是委托类型，这意味着它是表示方法签名的类型。有关详细信息，请参阅 MSDN。在您的情况下，您应该创建一个
IComparer对象，或者让您的Stuff对象实现IComparable或IComparable>（如果可能）。To answer your first question, the reason the method name can be passed is because
Comparison<T>is a delegate type, meaning it is a type representing a method signature. See MSDN for details.In your case, you should either create an
IComparerobject or have yourStuffobject implementIComparableorIComparable<T>(if possible).我认为您只需使用此重载。它使用 比较
来自链接：
EDIT
那么
ListView呢，正如您也注意到的那样，它实现了IComparer而不Comparison，因此您不能只将委托传递给它。I think you simply use this overload. which uses Comparison
From link:
EDIT
What about
ListView, as you noticed too, it implementsIComparerand notComparison, so you can not just pass a delegate to it.