10

目前我正在开发 WPF 应用程序（使用 MVVM），其中我在DataGridView.

<DataGrid RowHeaderWidth="0" ItemsSource="{Binding PartsList,UpdateSourceTrigger=PropertyChanged}" AutoGenerateColumns="False">
    <DataGrid.Columns>
        <DataGridTextColumn Header="Item Name" IsReadOnly="True" Width="*" Binding="{Binding ProductName}"></DataGridTextColumn>
        <DataGridTextColumn Header="Model Name" IsReadOnly="True" Width="*" Binding="{Binding CarModelName}"></DataGridTextColumn>
        <DataGridTextColumn Header="Company Name" IsReadOnly="True" Width="*" Binding="{Binding CompanName}"></DataGridTextColumn>
        <DataGridTextColumn Header="Price" IsReadOnly="True" Width="*" Binding="{Binding Rate}">
    </DataGrid.Columns>
</DataGrid>

这里 PartsList 是一个ObservableCollection实体 Part。

现在我想将自定义列添加到DataGrid显示折扣的列和显示净额的另一列。我怎样才能做到这一点？

请给出一个好主意，因为我需要处理数千条记录，所以性能对我来说非常重要。

先感谢您。

4

3 回答 3

1

尝试在以下Loaded事件中添加列DataGrid：

private void DataGrid_Loaded_1(object sender, RoutedEventArgs e)
{
    dataGrid.Columns.Add((DataGridTextColumn)this.Resources["DiscountColumn"]);
    dataGrid.Columns.Add((DataGridTextColumn)this.Resources["NetAmountColumn"]);

    //Alternatively you can create columns in .cs like

    dataGrid.Columns.Add(new DataGridTextColumn() { Header = "Dicount", Binding = new Binding("Discount") });
    dataGrid.Columns.Add(new DataGridTextColumn() { Header = "Net Amount", Binding = new Binding("NetAmount") });
}

<Window.Resources>
    <DataGridTextColumn x:Key="DiscountColumn" Header="Discount" IsReadOnly="True" Width="*" Binding="{Binding Discount}"/>
    <DataGridTextColumn x:Key="NetAmountColumn" Header="Net Amount" IsReadOnly="True" Width="*" Binding="{Binding NetAmount}"/>
</Window.Resources>

<DataGrid RowHeaderWidth="0" x:Name="dataGrid" Loaded="DataGrid_Loaded_1" />
于 2013-08-09T17:52:25.823 回答
0

这是一篇旧帖子，但我已经做了类似的事情MVVM，WPF所以我想我会花掉我的两分钱。

我无法给出任何关于它将如何执行的真实指示，但是我们还没有看到在ItemSource.

抱歉，这将是一段冗长的代码展示，但我会尝试将其分解，以便于理解。

最终你需要做的是创建一个Attached Behavior。

这是我的：

行为类

这完成了创建实际列的核心工作，并DataGrid根据ColumnsSource您绑定的列将它们添加到您的列中。

public class DataGridColumnCollectionBehavior
{
    private object columnsSource;
    private DataGrid dataGrid;

    public DataGridColumnCollectionBehavior(DataGrid dataGrid)
    {
        this.dataGrid = dataGrid;
    }

    public object ColumnsSource
    {
        get { return this.columnsSource; }
        set
        {
            object oldValue = this.columnsSource;
            this.columnsSource = value;
            this.ColumnsSourceChanged(oldValue, this.columnsSource);
        }
    }

    public string DisplayMemberFormatMember { get; set; }

    public string DisplayMemberMember { get; set; }

    public string FontWeightBindingMember { get; set; }

    public string FontWeightMember { get; set; }

    public string HeaderTextMember { get; set; }

    public string IsEditableMember { get; set; }

    public string SortMember { get; set; }

    public string TextAlignmentMember { get; set; }

    public string TextColourMember { get; set; }

    public string WidthMember { get; set; }

    private void AddHandlers(ICollectionView collectionView)
    {
        collectionView.CollectionChanged += this.ColumnsSource_CollectionChanged;
    }

    private void ColumnsSource_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        ICollectionView view = sender as ICollectionView;

        if (this.dataGrid == null)
        {
            return;
        }

        switch (e.Action)
        {
            case NotifyCollectionChangedAction.Add:
                for (int i = 0; i < e.NewItems.Count; i++)
                {
                    DataGridColumn column = CreateColumn(e.NewItems[i]);
                    dataGrid.Columns.Insert(e.NewStartingIndex + i, column);
                }
                break;
            case NotifyCollectionChangedAction.Move:
                List<DataGridColumn> columns = new List<DataGridColumn>();

                for (int i = 0; i < e.OldItems.Count; i++)
                {
                    DataGridColumn column = dataGrid.Columns[e.OldStartingIndex + i];
                    columns.Add(column);
                }

                for (int i = 0; i < e.NewItems.Count; i++)
                {
                    DataGridColumn column = columns[i];
                    dataGrid.Columns.Insert(e.NewStartingIndex + i, column);
                }
                break;
            case NotifyCollectionChangedAction.Remove:
                for (int i = 0; i < e.OldItems.Count; i++)
                {
                    dataGrid.Columns.RemoveAt(e.OldStartingIndex);
                }
                break;
            case NotifyCollectionChangedAction.Replace:
                for (int i = 0; i < e.NewItems.Count; i++)
                {
                    DataGridColumn column = CreateColumn(e.NewItems[i]);

                    dataGrid.Columns[e.NewStartingIndex + i] = column;
                }
                break;
            case NotifyCollectionChangedAction.Reset:
                dataGrid.Columns.Clear();
                CreateColumns(sender as ICollectionView);
                break;
            default:
                break;
        }
    }

    private void ColumnsSourceChanged(object oldValue, object newValue)
    {
        if (this.dataGrid != null)
        {
            dataGrid.Columns.Clear();

            if (oldValue != null)
            {
                ICollectionView view = CollectionViewSource.GetDefaultView(oldValue);

                if (view != null)
                {
                    this.RemoveHandlers(view);
                }
            }

            if (newValue != null)
            {
                ICollectionView view = CollectionViewSource.GetDefaultView(newValue);

                if (view != null)
                {
                    this.AddHandlers(view);

                    this.CreateColumns(view);
                }
            }
        }
    }

    private DataGridColumn CreateColumn(object columnSource)
    {
        DataGridColumn column = new DataGridTemplateColumn();

        var textBlockFactory = new FrameworkElementFactory(typeof(TextBlock));
        ((DataGridTemplateColumn)column).CellTemplate = new DataTemplate { VisualTree = textBlockFactory };
        textBlockFactory.SetValue(TextBlock.MarginProperty, new Thickness(3));

        if (!string.IsNullOrWhiteSpace(this.FontWeightBindingMember))
        {
            string propertyName = GetPropertyValue(columnSource, this.FontWeightBindingMember) as string;

            textBlockFactory.SetBinding(TextBlock.FontWeightProperty, new Binding(propertyName));
        }
        else if (!string.IsNullOrWhiteSpace(this.FontWeightMember))
        {
            textBlockFactory.SetValue(TextBlock.FontWeightProperty, (FontWeight)GetPropertyValue(columnSource, this.FontWeightMember));
        }

        if (!string.IsNullOrWhiteSpace(this.SortMember))
        {
            column.SortMemberPath = GetPropertyValue(columnSource, this.SortMember) as string;
        }

        if (!string.IsNullOrEmpty(this.DisplayMemberMember))
        {
            string propertyName = GetPropertyValue(columnSource, this.DisplayMemberMember) as string;

            string format = null;

            if (!string.IsNullOrEmpty(this.DisplayMemberFormatMember))
            {
                format = GetPropertyValue(columnSource, this.DisplayMemberFormatMember) as string;
            }

            if (string.IsNullOrEmpty(format))
            {
                format = "{0}";
            }

            textBlockFactory.SetBinding(TextBlock.TextProperty, new Binding(propertyName) { StringFormat = format });

            // If there is no sort member defined default to the display member.
            if (string.IsNullOrWhiteSpace(column.SortMemberPath))
            {
                column.SortMemberPath = propertyName;
            }
        }

        if (!string.IsNullOrWhiteSpace(this.TextAlignmentMember))
        {
            textBlockFactory.SetValue(TextBlock.TextAlignmentProperty, GetPropertyValue(columnSource, this.TextAlignmentMember));
        }

        if (!string.IsNullOrEmpty(this.HeaderTextMember))
        {
            column.Header = GetPropertyValue(columnSource, this.HeaderTextMember);
        }

        if (!string.IsNullOrWhiteSpace(this.TextColourMember))
        {
            string propertyName = GetPropertyValue(columnSource, this.TextColourMember) as string;
            textBlockFactory.SetBinding(TextBlock.ForegroundProperty, new Binding(propertyName));
        }

        if (!string.IsNullOrEmpty(this.WidthMember))
        {
            double width = (double)GetPropertyValue(columnSource, this.WidthMember);
            column.Width = width;
        }

        return column;
    }

    private void CreateColumns(ICollectionView collectionView)
    {
        foreach (object item in collectionView)
        {
            DataGridColumn column = this.CreateColumn(item);

            this.dataGrid.Columns.Add(column);
        }
    }

    private object GetPropertyValue(object obj, string propertyName)
    {
        object returnVal = null;

        if (obj != null)
        {
            PropertyInfo prop = obj.GetType().GetProperty(propertyName);

            if (prop != null)
            {
                returnVal = prop.GetValue(obj, null);
            }
        }

        return returnVal;
    }

    private void RemoveHandlers(ICollectionView collectionView)
    {
        collectionView.CollectionChanged -= this.ColumnsSource_CollectionChanged;
    }
}

访问器类

这是您在 XAML 文件中使用的类，用于创建Bindings.

public static class DataGridColumnCollection
{
    public static readonly DependencyProperty ColumnCollectionBehaviourProperty =
        DependencyProperty.RegisterAttached("ColumnCollectionBehaviour", typeof(DataGridColumnCollectionBehaviour), typeof(DataGridColumnCollection), new UIPropertyMetadata(null));

    public static readonly DependencyProperty ColumnsSourceProperty =
        DependencyProperty.RegisterAttached("ColumnsSource", typeof(object), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.ColumnsSourcePropertyChanged));

    public static readonly DependencyProperty DisplayMemberFormatMemberProperty =
        DependencyProperty.RegisterAttached("DisplayMemberFormatMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.DisplayMemberFormatMemberChanged));

    public static readonly DependencyProperty DisplayMemberMemberProperty =
        DependencyProperty.RegisterAttached("DisplayMemberMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.DisplayMemberMemberChanged));

    public static readonly DependencyProperty FontWeightBindingMemberProperty =
        DependencyProperty.RegisterAttached("FontWeightBindingMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.FontWeightBindingMemberChanged));

    public static readonly DependencyProperty FontWeightMemberProperty =
        DependencyProperty.RegisterAttached("FontWeightMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.FontWeightMemberChanged));

    public static readonly DependencyProperty IsEditableMemberProperty =
        DependencyProperty.RegisterAttached("IsEditableMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.IsEditableMemberChanged));

    public static readonly DependencyProperty HeaderTextMemberProperty =
        DependencyProperty.RegisterAttached("HeaderTextMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.HeaderTextMemberChanged));

    public static readonly DependencyProperty SortMemberProperty =
        DependencyProperty.RegisterAttached("SortMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.SortMemberChanged));

    public static readonly DependencyProperty TextAlignmentMemberProperty =
        DependencyProperty.RegisterAttached("TextAlignmentMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.TextAlignmentMemberChanged));

    public static readonly DependencyProperty TextColourMemberProperty =
        DependencyProperty.RegisterAttached("TextColourMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.TextColourMemberChanged));

    public static readonly DependencyProperty WidthMemberProperty =
        DependencyProperty.RegisterAttached("WidthMember", typeof(string), typeof(DataGridColumnCollection), new UIPropertyMetadata(null, DataGridColumnCollection.WidthMemberChanged));

    public static DataGridColumnCollectionBehaviour GetColumnCollectionBehaviour(DependencyObject obj)
    {
        return (DataGridColumnCollectionBehaviour)obj.GetValue(ColumnCollectionBehaviourProperty);
    }

    public static void SetColumnCollectionBehaviour(DependencyObject obj, DataGridColumnCollectionBehaviour value)
    {
        obj.SetValue(ColumnCollectionBehaviourProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(DataGrid))]
    public static object GetColumnsSource(DependencyObject obj)
    {
        return (object)obj.GetValue(ColumnsSourceProperty);
    }

    [AttachedPropertyBrowsableForType(typeof(DataGrid))]
    public static void SetColumnsSource(DependencyObject obj, ObservableCollection<DataGridColumn> value)
    {
        obj.SetValue(ColumnsSourceProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetDisplayMemberFormatMember(DependencyObject obj)
    {
        return (string)obj.GetValue(DisplayMemberFormatMemberProperty);
    }

    public static void SetDisplayMemberFormatMember(DependencyObject obj, string value)
    {
        obj.SetValue(DisplayMemberFormatMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetDisplayMemberMember(DependencyObject obj)
    {
        return (string)obj.GetValue(DisplayMemberMemberProperty);
    }

    public static void SetDisplayMemberMember(DependencyObject obj, string value)
    {
        obj.SetValue(DisplayMemberMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetFontWeightBindingMember(DependencyObject obj)
    {
        return (string)obj.GetValue(FontWeightBindingMemberProperty);
    }

    public static void SetFontWeightBindingMember(DependencyObject obj, string value)
    {
        obj.SetValue(FontWeightBindingMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetFontWeightMember(DependencyObject obj)
    {
        return (string)obj.GetValue(FontWeightMemberProperty);
    }

    public static void SetFontWeightMember(DependencyObject obj, string value)
    {
        obj.SetValue(FontWeightMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetTextAlignmentMember(DependencyObject obj)
    {
        return (string)obj.GetValue(TextAlignmentMemberProperty);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static void SetTextAlignmentMember(DependencyObject obj, string value)
    {
        obj.SetValue(TextAlignmentMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetTextColourMember(DependencyObject obj)
    {
        return (string)obj.GetValue(TextColourMemberProperty);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static void SetTextColourMember(DependencyObject obj, string value)
    {
        obj.SetValue(TextColourMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(DataGrid))]
    public static string GetHeaderTextMember(DependencyObject obj)
    {
        return (string)obj.GetValue(HeaderTextMemberProperty);
    }

    [AttachedPropertyBrowsableForType(typeof(DataGrid))]
    public static void SetHeaderTextMember(DependencyObject obj, string value)
    {
        obj.SetValue(HeaderTextMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetWidthMember(DependencyObject obj)
    {
        return (string)obj.GetValue(WidthMemberProperty);
    }

    public static void SetWidthMember(DependencyObject obj, string value)
    {
        obj.SetValue(WidthMemberProperty, value);
    }

    [AttachedPropertyBrowsableForType(typeof(GridView))]
    public static string GetSortMember(DependencyObject obj)
    {
        return (string)obj.GetValue(SortMemberProperty);
    }

    public static void SetSortMember(DependencyObject obj, string value)
    {
        obj.SetValue(SortMemberProperty, value);
    }

    private static void ColumnsSourcePropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).ColumnsSource = e.NewValue;
    }

    private static void DisplayMemberFormatMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).DisplayMemberFormatMember = e.NewValue as string;
    }

    private static void DisplayMemberMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).DisplayMemberMember = e.NewValue as string;
    }

    private static void FontWeightBindingMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).FontWeightBindingMember = e.NewValue as string;
    }

    private static void FontWeightMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).FontWeightMember = e.NewValue as string;
    }

    private static void IsEditableMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).IsEditableMember = e.NewValue as string;
    }

    private static void HeaderTextMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).HeaderTextMember = e.NewValue as string;
    }

    private static void SortMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).SortMember = e.NewValue as string;
    }

    private static void TextAlignmentMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).TextAlignmentMember = e.NewValue as string;
    }

    private static void TextColourMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).TextColourMember = e.NewValue as string;
    }

    private static void WidthMemberChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        DataGridColumnCollection.GetOrCreateBehaviour(sender).WidthMember = e.NewValue as string;
    }

    private static DataGridColumnCollectionBehaviour GetOrCreateBehaviour(DependencyObject source)
    {
        DataGridColumnCollectionBehaviour behaviour = DataGridColumnCollection.GetColumnCollectionBehaviour(source);

        if (behaviour == null)
        {
            behaviour = new DataGridColumnCollectionBehaviour(source as DataGrid);

            DataGridColumnCollection.SetColumnCollectionBehaviour(source, behaviour);
        }

        return behaviour;
    }
}

示例 XAML 用法

现在我们实际上开始使用它。

<DataGrid behaviors:DataGridColumnCollection.ColumnsSource="{Binding ColumnHeaders}"
          behaviors:DataGridColumnCollection.DisplayMemberFormatMember="Format"                         behaviors:DataGridColumnCollection.DisplayMemberMember="DisplayMember"
                      behaviors:DataGridColumnCollection.FontWeightBindingMember="FontWeightMember"
                      behaviors:DataGridColumnCollection.HeaderTextMember="Header"
                      behaviors:DataGridColumnCollection.SortMember="SortMember"
                      behaviors:DataGridColumnCollection.TextAlignmentMember="TextAlignment"
                      behaviors:DataGridColumnCollection.TextColourMember="TextColourMember"
                      behaviors:DataGridColumnCollection.WidthMember="Width"
                      ItemsSource="{Binding Items}">

列标题类

这只是我描述列的“简单”类。

public class ColumnHeaderDescriptor
{
    public string DisplayMember { get; set; }

    public string FontWeightMember { get; set; }

    public string Format { get; set; }

    public string Header { get; set; }

    public string SortMember { get; set; }

    public TextAlignment TextAlignment { get; set; }

    public string TextColourMember { get; set; }

    public double Width { get; set; }
}

实例化列

这就是我创建它们的方式。

this.ColumnHeaders.Add(new ColumnHeaderDescriptor { Header = Properties.Resources.Name, DisplayMember = "ItemName", Width = 250 });
this.ColumnHeaders.Add(new ColumnHeaderDescriptor { Header = Properties.Resources.ManufPartNumber, DisplayMember = "ManufPartNumber", Width = 150 });
this.ColumnHeaders.Add(new ColumnHeaderDescriptor { Header = Properties.Resources.LastUnitPrice, DisplayMember = "UnitPriceString", SortMember = "UnitPrice", Width = 90 });
this.ColumnHeaders.Add(new ColumnHeaderDescriptor { Header = Properties.Resources.AssetType, DisplayMember = "AssetType", Width = 100 });
this.ColumnHeaders.Add(new ColumnHeaderDescriptor { Header = Properties.Resources.Quantity, DisplayMember = "QuantityString", SortMember = "Quantity", Width = 80 });

结论

现在我明白这可能并不完全MVVM，但最终我们必须做出牺牲才能完成工作。这将允许您从视图模型中动态创建列并显示不同的信息。

我的解决方案相当复杂，我不能完全相信。我确信我从现有的 StackOverflow 答案中得到了起点，但是我不知道现在在哪里。考虑到它的复杂性，允许消费者确定许多不同的东西，比如文本颜色等。这对于其他解决方案来说很可能是矫枉过正，如果你不需要它们，你可以删除不必要的属性。

于 2018-09-04T19:43:41.837 回答
0

假设您为模型使用实体框架；使用基于基类计算的属性获取器创建模型的部分类。确保您实现 INotifyPropertyChange，然后在新列中绑定 NetAmount 和 Discount 的新属性。

于 2020-05-28T08:47:11.480 回答