使用 datatrigger 设置我的列的值

Question

我有一个数据网格，我希望能够使用 XAML 检测我的列是否显示 0，并且在这种情况下将零替换为“-”。

这是我的数据网格：

<DataGrid  Style="{DynamicResource StyleDataGrid}"   ItemsSource="{Binding Path=_Data, UpdateSourceTrigger=PropertyChanged}" Margin="10,54,10,10" Name="dataGridView1" >
                <DataGrid.Columns>

                    <DataGridTextColumn Width="35" Binding="{Binding Path=Object.MyValue}" SortMemberPath="Object.MyValue" Header="" IsReadOnly="true">
                        <DataGridTextColumn.CellStyle>
                            <Style BasedOn="{StaticResource {x:Type DataGridCell}}" TargetType="DataGridCell">
                                <Setter Property="Foreground" Value="{Binding BrushTroisPts}"/>
                                <Style.Triggers>
                                    <DataTrigger Binding="{Binding Path=TextBlock.Text, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type TextBlock}}}" Value="0">
                                        <Setter Property="TextBlock.Text" Value="-"/>
                                    </DataTrigger>

                                </Style.Triggers>
                            </Style>
                        </DataGridTextColumn.CellStyle>
                    </DataGridTextColumn>
</DataGrid.Columns>
</DataGrid>

但这不起作用，我怎样才能使它起作用？

谢谢

Answer 1

您可以使用转换器来执行此操作。查看 DataGridTextColumn 上的绑定、MyConverter 的代码和注册转换器的 window.resources。我虚拟化了一些类来匹配你已经拥有的。

XAML：

<Window x:Class="WpfApplication3.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:app="clr-namespace:WpfApplication3"
        Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <Style TargetType="DataGrid" x:Key="StyleDataGrid" />
        <app:MyConverter x:Key="MyConverter" />
    </Window.Resources>
    <Grid>
        <DataGrid  Style="{DynamicResource StyleDataGrid}"   ItemsSource="{Binding Path=_Data, UpdateSourceTrigger=PropertyChanged}" Margin="10,54,10,10" Name="dataGridView1" >
            <DataGrid.Columns>
                <DataGridTextColumn Width="35" Binding="{Binding Path=Object.MyValue, Converter={StaticResource MyConverter}}" SortMemberPath="Object.MyValue" Header="" IsReadOnly="true">
                    <DataGridTextColumn.CellStyle>
                        <Style BasedOn="{StaticResource {x:Type DataGridCell}}" TargetType="DataGridCell">
                            <Setter Property="Foreground" Value="{Binding BrushTroisPts}"/>
                        </Style>
                    </DataGridTextColumn.CellStyle>
                </DataGridTextColumn>
            </DataGrid.Columns>
        </DataGrid>
    </Grid>
</Window>

代码（C#）：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApplication3
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public List<MyData> _Data { get; set; }
        public MainWindow()
        {
            InitializeComponent();
            _Data = new List<MyData>();
            for (int i = 0; i < 10; i++)
            {
                _Data.Add(new MyData(i.ToString()));
            }
            this.DataContext = this;
        }
    }

    //Object.MyValue

    public class MyData
    {
        public MyObject Object { get; set; }

        public MyData(string val)
        {
            Object = new MyObject(val);
        }
    }
    public class MyObject
    {
        public string MyValue { get; set; }

        public MyObject(string val)
        {
            MyValue = val;
        }
    }

    public class MyConverter : IValueConverter
    {

        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if ("0".Equals(value))
                return "-";
            return value;
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}