对ObservableCollection进行排序 - 最好的方法是什么？

I have a ObservableCollection , where MyData is a class with 4 properties i.e. int id, string name, bool IsSelected, string IsVisible.

我有一个ObservableCollection，其中MyData是一个具有4个属性的类，即int id，string name，bool IsSelected，string IsVisible。

This ObservableCollection is binded to a combobox with checkboxes(Cities data for example). Now, when the user checks the checkboxes then next time when he opens the drop down - all selections should come on top in ascending order by name.

此ObservableCollection绑定到带有复选框的组合框（例如，城市数据）。现在，当用户选中复选框时，下次打开下拉菜单时 - 所有选项都应按名称按升序排在最前面。

I have also implemented auto complete when the user types in 3 chars in the combobox, the drop down will open showing all the selections first, then then all the items starting from the 3 chars type in by the user.

当用户在组合框中键入3个字符时，我也实现了自动完成，下拉将打开，首先显示所有选择，然后由3个字符开始的所有项目由用户键入。

I have researched and implemented the following code and it is working fine, but i want to know whether this is the best approach or can i implement this in a better manner, code is :

我已经研究并实现了以下代码，它工作正常，但我想知道这是否是最好的方法，还是我能以更好的方式实现它，代码是：

        IEnumerable<MyData> sort;
        ObservableCollection<MyData> tempSortedCities = new ObservableCollection<MyData>();
        sort = City.OrderByDescending(item => item.IsSelected).ThenBy(item => item.Name.ToUpper()) ; 
       // City is my observablecollection<MyData> property in my Model binded to combobox in UI
        foreach (var item in sort)
            tempSortedCities.Add(item);


        City.Clear(); // City is my observablecollection<MyData> property in my Model
        City = tempSortedCities;
        tempSortedCities = null;
        sort = null;

Thanks in advance for your time !

在此先感谢您的时间！

1 个解决方案

#1

ICollectionView seems to be a perfect fit for this. It was designed specifically for sorting, filtering and grouping of a collection without modifying the original collection.

ICollectionView似乎非常适合这种情况。它专门用于对集合进行排序，过滤和分组，而无需修改原始集合。

You can get an instance of ICollectionView for your collection using the following code:

您可以使用以下代码获取集合的ICollectionView实例：

var sortedCities  = CollectionViewSource.GetDefaultView(City);

Then you can setup sorting by adding instances of SortDescription type to the ICollectionView.SortDescriptions collection:

然后，您可以通过将SortDescription类型的实例添加到ICollectionView.SortDescriptions集合来设置排序：

sortedCities.SortDescriptions.Add(new SortDescription("IsSelected", ListSortDirection.Descending));
sortedCities.SortDescriptions.Add(new SortDescription("Name", ListSortDirection.Ascending));

Then you can bind your ComboBox directly to the collection view (instead of City collection) and it will display already sorted data.

然后，您可以将ComboBox直接绑定到集合视图（而不是City集合），它将显示已排序的数据。

#1