关于DataTable的列名是什么，点数使其不适合WPF的DataGrid控件？ [英] What is it about DataTable Column Names with dots that makes them unsuitable for WPF's DataGrid control?

问题描述

运行这个，并且被困惑：

Run this, and be confused:

<Window x:Class="Data_Grids.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525">
    <StackPanel>
        <DataGrid
        Name="r1"
              ItemsSource="{Binding Path=.}">
        </DataGrid>
        <DataGrid
        Name="r2"
              ItemsSource="{Binding Path=.}">
        </DataGrid>
    </StackPanel>
</Window>

Codebehind：

Codebehind:

using System.Data;
using System.Windows;

namespace Data_Grids
{
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            DataTable dt1, dt2;
            dt1 = new DataTable();
            dt2 = new DataTable();
            dt1.Columns.Add("a-name", typeof(string));
            dt1.Columns.Add("b-name", typeof(string));
            dt1.Rows.Add(new object[] { 1, "Hi" });
            dt1.Rows.Add(new object[] { 2, "Hi" });
            dt1.Rows.Add(new object[] { 3, "Hi" });
            dt1.Rows.Add(new object[] { 4, "Hi" });
            dt1.Rows.Add(new object[] { 5, "Hi" });
            dt1.Rows.Add(new object[] { 6, "Hi" });
            dt1.Rows.Add(new object[] { 7, "Hi" });
            dt2.Columns.Add("a.name", typeof(string));
            dt2.Columns.Add("b.name", typeof(string));
            dt2.Rows.Add(new object[] { 1, "Hi" });
            dt2.Rows.Add(new object[] { 2, "Hi" });
            dt2.Rows.Add(new object[] { 3, "Hi" });
            dt2.Rows.Add(new object[] { 4, "Hi" });
            dt2.Rows.Add(new object[] { 5, "Hi" });
            dt2.Rows.Add(new object[] { 6, "Hi" });
            dt2.Rows.Add(new object[] { 7, "Hi" });
            r1.DataContext = dt1;
            r2.DataContext = dt2;
        }
    }
}

我会告诉你什么发生。顶部的数据网格填充有列标题和数据。底部的datagrid具有列标题，但所有行都为空。

I'll tell you what happens. The top datagrid is populated with column headers and data. The bottom datagrid has column headers but all the rows are blank.

推荐答案

第二个表的列名被绑定路径解析器错误地解释。在此示例运行时，查看调试输出，您可以看到自动生成的列已绑定到'a'和'b'而不是'a.name'和'b.name'

The full stop character in the column names of the second table are incorrectly interpreted by the binding path parser. Look at the debug output while this example is running and you can see that the auto-generated columns have been bound to 'a' and 'b' rather than 'a.name' and 'b.name'

System.Windows.Data Error: 40 : BindingExpression path error: 'a' property not found on 'object' ''DataRowView' ... etc.
System.Windows.Data Error: 40 : BindingExpression path error: 'b' property not found on 'object' ''DataRowView' ... etc.

有一些不同的字符在绑定路径中有特殊的含义，包括全停（'。'），斜杠（'/'），方括号（' ['，']'）和括号（'（'，'）'），括号将导致您的应用程序崩溃。可以通过用方括号围绕绑定路径来转义这些特殊字符。有关路径和字符转义的更多信息，请参见绑定声明概述

There are a number of different characters which have special meaning in a binding path including full stop ('.'), slash ('/'), square brackets ('[',']') and parenthesis ('(',')'), the parenthesis will cause your app to crash. These special characters can be escaped by surrounding the binding path with square brackets. More information about paths and character escaping can be found in the Binding Declarations Overview

要解决这个问题，您必须设置AutoGenerateColumns =False，并指定xaml中的列绑定：

To fix this you will have to set AutoGenerateColumns="False" and specify the column bindings in the xaml:

    <DataGrid
    x:Name="r2"
          ItemsSource="{Binding .}" AutoGenerateColumns="False">
        <DataGrid.Columns>
            <DataGridTextColumn Header="a.name" Binding="{Binding Path=[a.name]}" />
            <DataGridTextColumn Header="b.name" Binding="{Binding Path=[b.name]}" />
        </DataGrid.Columns>
    </DataGrid>

或编程方式在

        r2.AutoGenerateColumns = false;
        foreach( DataColumn column in dt2.Columns )
        {
            var gridColumn = new DataGridTextColumn()
            {
                Header = column.ColumnName,
                Binding = new Binding( "[" + column.ColumnName + "]" )
            };

            r2.Columns.Add( gridColumn );
        }

        r2.DataContext = dt2;

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