WPF 中的验证错误样式，类似于 Silverlight

Question

默认情况下，WPF 中的Validation.ErrorTemplate 只是一个红色小边框，没有任何ToolTip。

在 Silverlight 4 中，验证错误的样式很好，开箱即用。

以下是 Silverlight 4 和 WPF 中发生的验证错误的比较

Silverlight 4

WPF

请注意，与我认为的很棒的外观相比，WPF 版本的外观非常扁平、无聊。银光。

WPF 框架中是否存在任何类似的验证样式/模板，或者是否有人创建了样式漂亮的验证模板（如上面的 Silverlight 版本）？或者我必须从头开始创建它们？

如果有人想尝试一下，可以使用以下代码重现上面的验证错误，适用于 Silverlight 和 WPF

MainWindow/MainPage.xaml

<StackPanel Orientation="Horizontal" Margin="10" VerticalAlignment="Top">
    <TextBox Text="{Binding Path=TextProperty, Mode=TwoWay, ValidatesOnExceptions=True}"/>
    <Button Content="Tab To Me..." Margin="20,0,0,0"/>
</StackPanel>

MainWindow/MainPage.xaml.cs

public MainWindow/MainPage()
{
    InitializeComponent();
    this.DataContext = this;
}

private string _textProperty;
public string TextProperty
{
    get { return _textProperty; }
    set
    {
        if (value.Length > 5)
        {
            throw new Exception("Too many characters");
        }
        _textProperty = value;
    }
}

Answer 1

我研究了验证错误模板的 Silverlight 版本，并创建了它的 WPF 版本，如下所示

在帖子底部添加了一个动画 GIF，但完成后我发现它可能很烦人，因为其中移动的鼠标。让我知道是否应该删除它..:)

我使用了 MultiBinding 和 BooleanOrConverter 来显示“工具提示错误”，当 TextBox 具有键盘焦点或鼠标位于右上角。对于淡入动画，我使用了 DoubleAnimation 作为 Opacity 和 ThicknessAnimation 以及 BackEase/Margin 的 >EaseOut EasingFunction

可像这样使用

<TextBox Validation.ErrorTemplate="{StaticResource errorTemplateSilverlightStyle}" />

errorTemplateSilverlightStyle

<ControlTemplate x:Key="errorTemplateSilverlightStyle">
    <StackPanel Orientation="Horizontal">
        <Border BorderThickness="1" BorderBrush="#FFdc000c" CornerRadius="0.7"
                VerticalAlignment="Top">
            <Grid>
                <Polygon x:Name="toolTipCorner"
                         Grid.ZIndex="2"
                         Margin="-1"
                         Points="6,6 6,0 0,0" 
                         Fill="#FFdc000c" 
                         HorizontalAlignment="Right" 
                         VerticalAlignment="Top"
                         IsHitTestVisible="True"/>
                <Polyline Grid.ZIndex="3"
                          Points="7,7 0,0" Margin="-1" HorizontalAlignment="Right" 
                          StrokeThickness="1.5"
                          StrokeEndLineCap="Round"
                          StrokeStartLineCap="Round"
                          Stroke="White"
                          VerticalAlignment="Top"
                          IsHitTestVisible="True"/>
                <AdornedElementPlaceholder x:Name="adorner"/>
            </Grid>
        </Border>
        <Border x:Name="errorBorder" Background="#FFdc000c" Margin="1,0,0,0"
                Opacity="0" CornerRadius="1.5"
                IsHitTestVisible="False"
                MinHeight="24" MaxWidth="267">
            <Border.Effect>
                <DropShadowEffect ShadowDepth="2.25" 
                                  Color="Black" 
                                  Opacity="0.4"
                                  Direction="315"
                                  BlurRadius="4"/>
            </Border.Effect>
            <TextBlock Text="{Binding ElementName=adorner,
                                      Path=AdornedElement.(Validation.Errors)[0].ErrorContent}"
                       Foreground="White" Margin="8,3,8,3" TextWrapping="Wrap"/>
        </Border>
    </StackPanel>
    <ControlTemplate.Triggers>
        <DataTrigger Value="True">
            <DataTrigger.Binding>
                <MultiBinding Converter="{StaticResource BooleanOrConverter}">
                    <Binding ElementName="adorner" Path="AdornedElement.IsKeyboardFocused" />
                    <Binding ElementName="toolTipCorner" Path="IsMouseOver"/>
                </MultiBinding>
            </DataTrigger.Binding>
            <DataTrigger.EnterActions>
                <BeginStoryboard x:Name="fadeInStoryboard">
                    <Storyboard>
                        <DoubleAnimation Duration="00:00:00.15"
                                         Storyboard.TargetName="errorBorder"
                                         Storyboard.TargetProperty="Opacity"
                                         To="1"/>
                        <ThicknessAnimation Duration="00:00:00.15"
                                            Storyboard.TargetName="errorBorder"
                                            Storyboard.TargetProperty="Margin"
                                            FillBehavior="HoldEnd"
                                            From="1,0,0,0"
                                            To="5,0,0,0">
                            <ThicknessAnimation.EasingFunction>
                                <BackEase EasingMode="EaseOut" Amplitude="2"/>
                            </ThicknessAnimation.EasingFunction>
                        </ThicknessAnimation>
                    </Storyboard>
                </BeginStoryboard>
            </DataTrigger.EnterActions>
            <DataTrigger.ExitActions>
                <StopStoryboard BeginStoryboardName="fadeInStoryboard"/>
                <BeginStoryboard x:Name="fadeOutStoryBoard">
                    <Storyboard>
                        <DoubleAnimation Duration="00:00:00"
                                         Storyboard.TargetName="errorBorder"
                                         Storyboard.TargetProperty="Opacity"
                                         To="0"/>
                    </Storyboard>
                </BeginStoryboard>
            </DataTrigger.ExitActions>
        </DataTrigger>
    </ControlTemplate.Triggers>
</ControlTemplate>

BooleanOrConverter

public class BooleanOrConverter : IMultiValueConverter
{
    public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        foreach (object value in values)
        {
            if ((bool)value == true)
            {
                return true;
            }
        }
        return false;
    }
    public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotSupportedException();
    }
}

Answer 2

这个答案只是扩展了 Fredrik Hedblad 的出色答案。作为 WPF 和 XAML 的新手，Fredrik 的答案充当了定义我希望如何在应用程序中显示验证错误的跳板。虽然下面的 XAML 对我有用，但它是一项正在进行的工作。我还没有完全测试它，并且我很容易承认我无法完全解释每个标签。有了这些警告，我希望这对其他人有用。

而动画 TextBlock< /a> 是一个很好的方法，它有两个我想解决的缺点。

1. 首先，正如 Brent 的评论所指出的，文本受到所属窗口边框的约束，因此如果无效控件位于窗口的边缘，文本被切断。 Fredrik 建议的解决方案是将其显示在“窗外”。这对我来说很有意义。
2. 其次，显示 TextBlock 右侧的无效控制并不总是最优的。例如，假设 TextBlock 用于指定要打开的特定文件，并且其右侧有一个“浏览”按钮。如果用户键入不存在的文件，则会出现错误 TextBlock 将覆盖浏览按钮，并可能阻止用户单击它来更正错误。对我来说有意义的是将错误消息显示在无效控件的右侧对角线上。这完成了两件事。首先，它避免隐藏无效控件右侧的任何伴随控件。它还具有 toolTipCorner 指向错误消息的视觉效果。

这是我完成开发的对话框。

如您所见，有两个 TextBox 需要验证的控件。两者都相对靠近窗口的右边缘，因此很长的错误消息可能会被裁剪掉。请注意第二个 TextBox 有一个浏览按钮，我不想在发生错误时隐藏该按钮。

下面是使用我的实现时出现的验证错误。

从功能上讲，它与 Fredrik 的实现非常相似。如果 文本框 具有焦点，错误将可见。一旦失去焦点，错误就会消失。如果用户将鼠标悬停在 toolTipCorner 上，无论 TextBox 是否具有焦点。还有一些外观上的变化，例如 toolTipCorner 增大了 50%（9 像素与 6 像素）。

当然，明显的区别是我的实现使用 弹出窗口显示错误。这解决了第一个缺点，因为 Popup 在自己的窗口中显示其内容，因此它不受对话框边框的限制。但是，使用 Popup 确实提出了一些需要克服的挑战。

1. 从测试和在线讨论来看，Popup 被视为最顶层窗口。因此，即使我的应用程序被另一个应用程序隐藏，弹出窗口 仍然可见。这是不太理想的行为。
2. 另一个问题是，如果用户碰巧移动或调整对话框大小，而 弹出窗口可见，弹出窗口没有重新定位自己以维持其相对于无效控件的位置。

幸运的是，这两个挑战都已得到解决。

这是代码。欢迎评论和完善！

---

• 文件：ErrorTemplateSilverlightStyle.xaml
• 命名空间：MyApp.Application.UI.Templates
• 程序集：MyApp.Application.UI.dll

<ResourceDictionary
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
  xmlns:behaviors="clr-namespace:MyApp.Application.UI.Behaviors">

  <ControlTemplate x:Key="ErrorTemplateSilverlightStyle">
    <StackPanel Orientation="Horizontal">
      <!-- Defines TextBox outline border and the ToolTipCorner -->
      <Border x:Name="border" BorderThickness="1.25"
                              BorderBrush="#FFDC000C">
        <Grid>
          <Polygon x:Name="toolTipCorner"
                   Grid.ZIndex="2"
                   Margin="-1"
                   Points="9,9 9,0 0,0"
                   Fill="#FFDC000C"
                   HorizontalAlignment="Right"
                   VerticalAlignment="Top"
                   IsHitTestVisible="True"/>
          <Polyline Grid.ZIndex="3"
                    Points="10,10 0,0"
                    Margin="-1"
                    HorizontalAlignment="Right"
                    StrokeThickness="1.5"
                    StrokeEndLineCap="Round"
                    StrokeStartLineCap="Round"
                    Stroke="White"
                    VerticalAlignment="Top"
                    IsHitTestVisible="True"/>
          <AdornedElementPlaceholder x:Name="adorner"/>
        </Grid>
      </Border>
      <!-- Defines the Popup -->
      <Popup x:Name="placard"
             AllowsTransparency="True"
             PopupAnimation="Fade"
             Placement="Top"
             PlacementTarget="{Binding ElementName=toolTipCorner}"
             PlacementRectangle="10,-1,0,0">
        <!-- Used to reposition Popup when dialog moves or resizes -->
        <i:Interaction.Behaviors>
          <behaviors:RepositionPopupBehavior/>
        </i:Interaction.Behaviors>
        <Popup.Style>
          <Style TargetType="{x:Type Popup}">
            <Style.Triggers>
              <!-- Shows Popup when TextBox has focus -->
              <DataTrigger Binding="{Binding ElementName=adorner, Path=AdornedElement.IsFocused}"
                           Value="True">
                <Setter Property="IsOpen" Value="True"/>
              </DataTrigger>
              <!-- Shows Popup when mouse hovers over ToolTipCorner -->
              <DataTrigger Binding="{Binding ElementName=toolTipCorner, Path=IsMouseOver}"
                           Value="True">
                <Setter Property="IsOpen" Value="True"/>
              </DataTrigger>
              <!-- Hides Popup when window is no longer active -->
              <DataTrigger Binding="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Window}}, Path=IsActive}"
                           Value="False">
                <Setter Property="IsOpen" Value="False"/>
              </DataTrigger>
            </Style.Triggers>
          </Style>
        </Popup.Style>
        <Border x:Name="errorBorder"
                Background="#FFDC000C"
                Margin="0,0,8,8"
                Opacity="1"
                CornerRadius="4"
                IsHitTestVisible="False"
                MinHeight="24"
                MaxWidth="267">
          <Border.Effect>
            <DropShadowEffect ShadowDepth="4"
                              Color="Black"
                              Opacity="0.6"
                              Direction="315"
                              BlurRadius="4"/>
          </Border.Effect>
          <TextBlock Text="{Binding ElementName=adorner, Path=AdornedElement.(Validation.Errors).CurrentItem.ErrorContent}"
                     Foreground="White"
                     Margin="8,3,8,3"
                     TextWrapping="Wrap"/>
        </Border>
      </Popup>
    </StackPanel>
  </ControlTemplate>

</ResourceDictionary>

---

• 文件：RepositionPopupBehavior.cs
• 命名空间：MyApp.Application.UI.Behaviors
• 程序集：MyApp.Application.UI.dll

（注意：这需要 EXPRESSION BLEND 4 System.Windows.Interactivity 程序集）< /强>

using System;
using System.Windows;
using System.Windows.Controls.Primitives;
using System.Windows.Interactivity;

namespace MyApp.Application.UI.Behaviors
{
    /// <summary>
    /// Defines the reposition behavior of a <see cref="Popup"/> control when the window to which it is attached is moved or resized.
    /// </summary>
    /// <remarks>
    /// This solution was influenced by the answers provided by <see href="https://stackoverflow.com/users/262204/nathanaw">NathanAW</see> and
    /// <see href="https://stackoverflow.com/users/718325/jason">Jason</see> to
    /// <see href="https://stackoverflow.com/questions/1600218/how-can-i-move-a-wpf-popup-when-its-anchor-element-moves">this</see> question.
    /// </remarks>
    public class RepositionPopupBehavior : Behavior<Popup>
    {
        #region Protected Methods

        /// <summary>
        /// Called after the behavior is attached to an <see cref="Behavior.AssociatedObject"/>.
        /// </summary>
        protected override void OnAttached()
        {
            base.OnAttached();
            var window = Window.GetWindow(AssociatedObject.PlacementTarget);
            if (window == null) { return; }
            window.LocationChanged += OnLocationChanged;
            window.SizeChanged     += OnSizeChanged;
            AssociatedObject.Loaded += AssociatedObject_Loaded;
        }

        void AssociatedObject_Loaded(object sender, RoutedEventArgs e)
        {
            //AssociatedObject.HorizontalOffset = 7;
            //AssociatedObject.VerticalOffset = -AssociatedObject.Height;
        }

        /// <summary>
        /// Called when the behavior is being detached from its <see cref="Behavior.AssociatedObject"/>, but before it has actually occurred.
        /// </summary>
        protected override void OnDetaching()
        {
            base.OnDetaching();
            var window = Window.GetWindow(AssociatedObject.PlacementTarget);
            if (window == null) { return; }
            window.LocationChanged -= OnLocationChanged;
            window.SizeChanged     -= OnSizeChanged;
            AssociatedObject.Loaded -= AssociatedObject_Loaded;
        }

        #endregion Protected Methods

        #region Private Methods

        /// <summary>
        /// Handles the <see cref="Window.LocationChanged"/> routed event which occurs when the window's location changes.
        /// </summary>
        /// <param name="sender">
        /// The source of the event.
        /// </param>
        /// <param name="e">
        /// An object that contains the event data.
        /// </param>
        private void OnLocationChanged(object sender, EventArgs e)
        {
            var offset = AssociatedObject.HorizontalOffset;
            AssociatedObject.HorizontalOffset = offset + 1;
            AssociatedObject.HorizontalOffset = offset;
        }

        /// <summary>
        /// Handles the <see cref="Window.SizeChanged"/> routed event which occurs when either then <see cref="Window.ActualHeight"/> or the
        /// <see cref="Window.ActualWidth"/> properties change value.
        /// </summary>
        /// <param name="sender">
        /// The source of the event.
        /// </param>
        /// <param name="e">
        /// An object that contains the event data.
        /// </param>
        private void OnSizeChanged(object sender, SizeChangedEventArgs e)
        {
            var offset = AssociatedObject.HorizontalOffset;
            AssociatedObject.HorizontalOffset = offset + 1;
            AssociatedObject.HorizontalOffset = offset;
        }

        #endregion Private Methods
    }
}

---

• 文件：ResourceLibrary.xaml
• 命名空间：MyApp.Application.UI
• 程序集：MyApp.Application.UI.dll

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

    <ResourceDictionary.MergedDictionaries>

        <!-- Styles -->
        ...

        <!-- Templates -->
        <ResourceDictionary Source="Templates/ErrorTemplateSilverlightStyle.xaml"/>

    </ResourceDictionary.MergedDictionaries>

    <!-- Converters -->
    ...

</ResourceDictionary>

---

• 文件：App.xaml
• 命名空间：MyApp.Application
• 程序集：MyApp.exe

<Application x:Class="MyApp.Application.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             StartupUri="Views\MainWindowView.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="/MyApp.Application.UI;component/ResourceLibrary.xaml"/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

---

• 文件：NewProjectView.xaml
• 命名空间：MyApp.Application.Views
• 程序集：MyApp.exe

<Window x:Class="MyApp.Application.Views.NewProjectView"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:views="clr-namespace:MyApp.Application.Views"
        xmlns:viewModels="clr-namespace:MyApp.Application.ViewModels"
        Title="New Project" Width="740" Height="480"
        WindowStartupLocation="CenterOwner">

  <!-- DATA CONTEXT -->
  <Window.DataContext>
    <viewModels:NewProjectViewModel/>
  </Window.DataContext>

  <!-- WINDOW GRID -->
  ...

  <Label x:Name="ProjectNameLabel"
         Grid.Column="0"
         Content="_Name:"
         Target="{Binding ElementName=ProjectNameTextBox}"/>
  <TextBox x:Name="ProjectNameTextBox"
           Grid.Column="2"
           Text="{Binding ProjectName,
                          Mode=TwoWay,
                          UpdateSourceTrigger=PropertyChanged,
                          ValidatesOnDataErrors=True}"
           Validation.ErrorTemplate="{StaticResource ErrorTemplateSilverlightStyle}"/>

  ...
</Window>

Answer 3

我在其中一个项目中创建了自定义错误装饰器，以在文本框下方显示错误装饰器，其中包含错误消息。您只需在文本框默认样式中设置属性“Validation.ErrorTemplate”，您可以将其保留在应用程序资源中，以便将其应用于应用程序中的所有文本框。

注意：我在这里使用了一些画笔，请将其替换为您自己的装饰信息所需的画笔。也许这会有所帮助：

<Setter Property="Validation.ErrorTemplate">
              <Setter.Value>
                <ControlTemplate>
                  <StackPanel>
                    <!--TextBox Error template-->
                    <Canvas Panel.ZIndex="1099">
                      <DockPanel>
                        <Border BorderBrush="{DynamicResource HighlightRedBackgroundBrush}" BorderThickness="2" Padding="1" CornerRadius="3">
                          <AdornedElementPlaceholder x:Name="ErrorAdorner" />
                        </Border>
                      </DockPanel>
                      <Popup IsOpen="True" AllowsTransparency="True" Placement="Bottom" PlacementTarget="{Binding ElementName=ErrorAdorner}" StaysOpen="False">
                        <Border Canvas.Bottom="4"
                Canvas.Left="{Binding Path=AdornedElement.ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Adorner}}}"
                BorderBrush="{DynamicResource HighlightRedBackgroundBrush}"
                BorderThickness="1"
                Padding="4"
                CornerRadius="5"
                Background="{DynamicResource ErrorBackgroundBrush}">
                          <StackPanel Orientation="Horizontal">
                            <ContentPresenter Width="24" Height="24" Content="{DynamicResource ExclamationIcon}" />
                            <TextBlock TextWrapping="Wrap"
                   Margin="4"
                   MaxWidth="250"
                   Text="{Binding Path=AdornedElement.(Validation.Errors)[0].ErrorContent, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Adorner}}}" />
                          </StackPanel>
                        </Border>
                      </Popup>
                    </Canvas>
                  </StackPanel>
                </ControlTemplate>
              </Setter.Value>
            </Setter>

Answer 4

当我尝试将其应用到我正在开发的 wpf 项目时，我遇到了一个问题。如果您在尝试运行项目时遇到以下问题：

“PresentationFramework.dll 中出现类型为‘System.Windows.Markup.XamlParseException’的异常，但未在用户代码中处理”，

您需要创建一个实例资源中的 booleanOrConverter 类（在 app.xaml 中）：

<validators:BooleanOrConverter x:Key="myConverter" />

另外不要忘记将命名空间添加到文件顶部（在应用程序标记中）：

xmlns：validators =“clr命名空间：ParcelRatesViewModel.Validators;程序集= ParcelRatesViewModel”