具有多个(失败的)ValidationRules的BindingGroup

我今天在工作中遇到了一个问题 BindingGroup 有多个 ValidationRule 同时发生故障的。问题是,我有一个 ArgumentException 从沸腾中冒出来 BindingGroup.ValidateWithoutUpdate 当我尝试确定是否有任何错误时(即设置 CanExecute 一个命令 false ).

我已经成功地将其提取到以下示例中(抱歉,它仍然跨越多个源,但我已经将所有相关部分都包含在一个新的WPF项目中,这些部分应该是可以复制/粘贴的):

<Window 
    x:Class="BindingGroupTest.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:l="clr-namespace:BindingGroupTest"
    xmlns:diag="clr-namespace:System.Diagnostics;assembly=WindowsBase"
    Title="Window1" Height="300" Width="300">

    <Window.BindingGroup>
        <BindingGroup Name="RootBindingGroup">
            <BindingGroup.ValidationRules>
                <l:TestRule1 />
                <l:TestRule2 />
            </BindingGroup.ValidationRules>
        </BindingGroup>
    </Window.BindingGroup>

    <StackPanel>
        <TextBox Text="{Binding 
            Path=Name, 
            BindingGroupName=RootBindingGroup,
            UpdateSourceTrigger=PropertyChanged,
            diag:PresentationTraceSources.TraceLevel=High}" />
        <TextBox Text="{Binding 
            Path=Age, 
            BindingGroupName=RootBindingGroup,
            UpdateSourceTrigger=PropertyChanged,
            diag:PresentationTraceSources.TraceLevel=High}" />
        <Button Content="Validate" Click="DoValidate" />
    </StackPanel>
</Window>

Window1.xaml.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
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 BindingGroupTest
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1 : Window
    {
        public Window1()
        {
            this.DataContext = new Person()
            {
                Name="Test",
                Age=30,
            };

            InitializeComponent();

            this.BindingGroup.BeginEdit();
        }

        private void DoValidate(object sender, RoutedEventArgs e)
        {
            try
            {
                if (!this.BindingGroup.ValidateWithoutUpdate())
                    MessageBox.Show("Validation failed!");
                else
                    MessageBox.Show("Validation passed!");
            }
            catch (Exception ex)
            {
                var msg = "While validating, caught exception: " + ex.Message;
                MessageBox.Show(msg);
            }
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace BindingGroupTest
{
    public class Person
    {
        public string Name { get; set; }
        public int Age { get; set; }
    }
}

测试规则1.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;

namespace BindingGroupTest
{
    public class TestRule1 : ValidationRule
    {
        public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
        {
            var p = ((BindingGroup)value).Items[0] as Person;
            if (p == null)
                return ValidationResult.ValidResult;

            if (p.Age < 0)
                return new ValidationResult(false, "Surely, you've been born yet!");

            return ValidationResult.ValidResult;
        }
    }
}

测试规则2.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;

namespace BindingGroupTest
{
    public class TestRule2 : ValidationRule
    {
        public override ValidationResult Validate(object value, System.Globalization.CultureInfo cultureInfo)
        {
            var p = ((BindingGroup)value).Items[0] as Person;
            if (p == null)
                return ValidationResult.ValidResult;

            if (string.IsNullOrEmpty(p.Name))
                return new ValidationResult(false, "What, no name?");

            return ValidationResult.ValidResult;
        }
    }
}

基本上,我的问题是如果两者 TestRule1 fail, I get an 参数异常 bubbling up when I call with message "Cannot have duplicates in this Collection", parameter name: "validationError". I dug around through the implementation of 绑定组 , and it seems that it is using itself as the second parameter to 验证错误 , which is the 绑定错误 parameter, which the underlying

对同一业务对象的不同属性进行操作的,将这些属性折叠为一个单独的属性是没有意义的 ). 另外,我能找到的每一个使用 绑定组 验证规则

是我做错了什么,还是这看起来像是一个错误 绑定组 实现,就像我现在想的那样。