c# - WPF 验证错误 : How to show in separate TextBlock, 不在工具提示中

Question

我认为我真的要疯了，但我找不到解决方案来显示验证错误，而不是在工具提示中，而是在与用户输入的文本框无关的单独文本 block 中。

我想要一个包含验证摘要的 TextBlock，与用户在哪个文本框中输入的内容无关。

您知道该行为的解决方案吗？

编辑: 我当前的实现看起来像这样:

<TextBox Margin="{StaticResource WinHorizontalMargin}" 
         Style="{StaticResource WinInputBoxNormalStyle}">
   <TextBox.Text>
      <Binding Path="AccessCode" Mode="TwoWay" UpdateSourceTrigger="PropertyChanged">
         <Binding.ValidationRules>
            <ValidationRules:MandatoryValidationRule Field="Access Code"/> 
         </Binding.ValidationRules>
      </Binding>
   </TextBox.Text>
</TextBox>

<!-- Content Error Message -->
<TextBlock Grid.Row="2" Grid.ColumnSpan="2" Text="{Binding Path=(Validation.Errors)[0].ErrorContent}">
</TextBlock>

谢谢 - 格哈德

Answer 1

您可以使用网格的 BindingGroup 并在用户提交表单时验证所有内容。

<Window x:Class="WpfApplication1.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:WpfApplication1="clr-namespace:WpfApplication1" Title="MainWindow" Height="350" Width="525">
    <Window.Resources>
        <WpfApplication1:ErrorsToMessageConverter x:Key="e2mConverter"/>
    </Window.Resources>
    <Grid x:Name="TheGrid">

        <Grid.BindingGroup>
            <BindingGroup Name="UserInputBindingGroup">
                <BindingGroup.ValidationRules>
                    <WpfApplication1:MandatoryValidationRule/>
                </BindingGroup.ValidationRules>
            </BindingGroup>
        </Grid.BindingGroup>

        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition />
            <RowDefinition />
        </Grid.RowDefinitions>
        <TextBox x:Name="theTextBox">
            <TextBox.Text>
                <Binding Path="AccessCode" Mode="TwoWay" UpdateSourceTrigger="PropertyChanged">                            
                </Binding>
            </TextBox.Text>
        </TextBox>

        <!-- Content Error Message -->
        <TextBlock Grid.Row="1" Text="{Binding ElementName=TheGrid, Path=(Validation.Errors), Converter={StaticResource e2mConverter}}">
        </TextBlock>

        <Button Grid.Row="2" Content="Submit" Click="Button_Click" />
    </Grid>
</Window>

按钮单击事件提交网格的 BindingGroup，如下所示:

private void Button_Click(object sender, RoutedEventArgs e)
{
    this.TheGrid.BindingGroup.CommitEdit();
}

Window 的 DataContext 设置为一个类

public class UserInputValues
{
    public string AccessCode { get; set; }
}

验证在 MandatoryValidationRule 类的 Validation 方法中进行

public override ValidationResult Validate(object value, CultureInfo cultureInfo)
{
    BindingGroup bindingGroup = (BindingGroup) value;
    UserInputValues userInputValues = (UserInputValues) bindingGroup.Items[0];


    object accessCode = bindingGroup.GetValue(userInputValues, "AccessCode");

    // Validation code here...

    return new ValidationResult(false, "No no no!");
}