Question

我正在尝试对ListCollectionView进行排序，但我无法让它发挥作用。我有自己的CustomSort会引发以下错误：

无法将类型'SceneComparer'隐式转换为'IComparer'。一个存在显式转换。（你错过了演员吗？）

这是我的比较器的样子：

public class SceneComparer : IComparer<Scene>
{
    // Assumes that a scene is either numeric, or numeric + alpha.
    private readonly Regex sceneRegEx = new Regex(@"(\d*)(\w*)", RegexOptions.Compiled);

    public int Compare(Scene x, Scene y)
    {
        var firstSceneMatch = this.sceneRegEx.Match(x.SceneNumber);

        var firstSceneNumeric = Convert.ToInt32(firstSceneMatch.Groups[1].Value);
        var firstSceneAlpha = firstSceneMatch.Groups[2].Value;

        var secondSceneMatch = this.sceneRegEx.Match(y.SceneNumber);

        var secondSceneNumeric = Convert.ToInt32(secondSceneMatch.Groups[1].Value);
        var secondSceneAlpha = secondSceneMatch.Groups[2].Value;

        if (firstSceneNumeric < secondSceneNumeric)
        {
            return -1;
        }

        if (firstSceneNumeric > secondSceneNumeric)
        {
            return 1;
        }

        return string.CompareOrdinal(firstSceneAlpha, secondSceneAlpha);
    }
}

这是ViewModel中的排序

private ListCollectionView _scenesNavigator;
public ListCollectionView ScenesNavigator
{
    get
    {
        _scenesNavigator = SceneCollectionView;
        _scenesNavigator.CustomSort = new SceneComparer(); ----> ERROR
        _scenesNavigator.IsLiveSorting = true;

        return _scenesNavigator;
    }
    set
    {
        _scenesNavigator = value; RaisePropertyChanged();
    }
}

public SourceViewModel()
{
        SceneCollectionView = Application.Current.Resources["SceneCollectionView"] as ListCollectionView;
}

我该如何解决这个问题？

Answer 1

CustomSort的类型为IComparer（msdn）。

以下是示例：

http://weblogs.asp.net/monikadyrda/wpf-listcollectionview-for-sorting-filtering-and-grouping

public class SortCreaturesByAge : IComparer
{
    public int Compare( object x, object y )
    {
        if( x as CreatureModel == null && y as CreatureModel == null )
        {
            throw new ArgumentException( "SortCreatures can 
                                    only sort CreatureModel objects." );
        }
        if( ((CreatureModel) x).Age > ((CreatureModel) y).Age )
        {
            return 1;
        }
        return -1;
    }
}

使用CustomSort对ListCollectionView进行排序

1 个答案: