WPF - 粗体字体出现问题

Question

所附的屏幕截图应该能让您清楚地了解我在说什么。我编写了一个小型 wpf 应用程序，可以使用我选择的任何图像创建“明信片”。然后，它可以将带有或不带有文本的图像保存为 jpg 格式，然后通过电子邮件发送。我采取以下步骤：

1. 调出文本输入表格（如图）
2. 单击“字体”按钮，可以选择（或更改）字体名称、大小和颜色。
3. 如果我不选择粗体，表格看起来就像屏幕截图（正确）。
4. 当我尝试将粗体文本添加到输入框和（通过绑定）明信片文本时，我的问题就出现了。

当文本框应该是唯一受影响的控件时，标签中的字体粗细和所有 3 个按钮都会变为粗体。只有粗细发生了变化——字体名称、大小和颜色保持不变。 这让我疯狂。想不通。我已经包含了我认为相关的代码。

来自表单的 xaml：

<UserControl x:Class="PostcardMVVM.Views.EditView" Style="{StaticResource ControlStyle}"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
         xmlns:local="clr-namespace:PostcardMVVM.ViewModel"
         mc:Ignorable="d" Width="800" Height="640" Loaded="UserControl_Loaded">

<!--<UserControl.DataContext>
    <editModel:EditViewModel/>
</UserControl.DataContext>-->

<!--<Grid>
    <Border Margin="68,67,60,67" BorderBrush="Black" BorderThickness="1" CornerRadius="10">
        <Border.Effect>
            <DropShadowEffect/>
        </Border.Effect>
        <Rectangle Fill="White" Stroke="Black" Margin="37,89,118,98" />
    </Border>
</Grid>-->

<Grid>
    <Grid.Effect>
        <DropShadowEffect Color="SlateGray" BlurRadius="10"/>
    </Grid.Effect>
    <Canvas x:Name="mainGrid" Margin="0,0,0,200" Background="White">
        <Image x:Name="imgvImage" Height="400" Width="400" Canvas.Left="255" Canvas.Top="20"/>
        <TextBlock x:Name="tblkText" IsEnabled="False" HorizontalAlignment="Center" TextWrapping="Wrap" Height="210" Canvas.Left="20" Canvas.Top="20"  
            VerticalAlignment="Top" Foreground="{Binding ElementName=txtText, Path=Foreground}"  Width="400" Text="{Binding ElementName=txtText, Path=Text}" Padding="10, 3, 10, 3" 
            FontFamily="{Binding ElementName=txtText, Path=FontFamily}" FontSize="{Binding ElementName=txtText, Path=FontSize}"  FontWeight="{Binding ElementName=txtText, Path=FontWeight}" 
                   RenderTransformOrigin="0.238,-2.2" Background="Transparent">
            <TextBlock.Effect>
                <DropShadowEffect ShadowDepth="2" Color="Black" BlurRadius="3" ></DropShadowEffect>
            </TextBlock.Effect>
            <TextBlock.LayoutTransform >
                <RotateTransform Angle = "-90" ></RotateTransform >
            </TextBlock.LayoutTransform >
        </TextBlock>
    </Canvas>
    <Canvas>
        <!--<Canvas.Resources>
        </Canvas.Resources>-->
        <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" Height="115" Canvas.Top="440" VerticalAlignment="Top" >
            <Label Margin="10,30,0,30" TabIndex="20" x:Name="Label1" VerticalContentAlignment="Center" Content="Enter Text:" 
                   Style="{Binding Source={StaticResource LabelStyle}}" RenderTransformOrigin="0.511,-2.5"/>
            <TextBox x:Name="txtText" TabIndex="0" Width="200" VerticalContentAlignment="Top" MinLines="1"
                MaxLines="3" AcceptsReturn="True" TextWrapping="Wrap" Margin="40,10,0,10"   
                BorderBrush="Black" BorderThickness="1" ToolTip="Type in message and hit enter to save postcard" KeyUp="txtText_KeyUp"/>
            <Button x:Name="btnFont" Content="Font" Width="75" Margin="45,35" Click="btnFont_Click" 
                    Style="{Binding Source={StaticResource ButtonStyle}}" IsDefault="True" Height="40" />
        </StackPanel>
        <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" Height="50" Canvas.Top="570" VerticalAlignment="Top">
            <Button Margin="10,0,0,0" Height="40" x:Name="btnEmail" Width="75" Content="Email" IsEnabled="false" Style="{Binding Source={StaticResource ButtonStyle}}" />
            <Button Margin="10,0,0,0" Height="40" x:Name="btnCancel" Width="75" Content="Cancel" Click="btnCancel_Click" Style="{Binding Source={StaticResource ButtonStyle}}"/>
        </StackPanel>
    </Canvas>
</Grid>

背后代码：

        private void btnFont_Click(object sender, RoutedEventArgs e)
    {
        FontDialog fontDialog1 = new FontDialog();  // try setting initial color here
        fontDialog1.ShowColor = true;
        
        var result = fontDialog1.ShowDialog();

        if (result == System.Windows.Forms.DialogResult.OK)
        {
            System.Drawing.Color fc = fontDialog1.Color;

            txtText.FontFamily = new swm.FontFamily(fontDialog1.Font.Name);
            txtText.FontSize = fontDialog1.Font.Size;
            txtText.FontWeight = FontWeight = fontDialog1.Font.Bold ? FontWeights.Bold : FontWeights.Regular;
            txtText.Foreground = new SolidColorBrush(Color.FromArgb(fc.A, fc.R, fc.G, fc.B));

            //tblkText.Foreground = new SolidColorBrush(Color.FromArgb(fc.A, fc.R, fc.G, fc.B));

            var bindingExpression = tblkText.GetBindingExpression(TextBlock.TextProperty);
            bindingExpression.UpdateSource();

            bindingExpression = tblkText.GetBindingExpression(TextBlock.FontFamilyProperty);
            bindingExpression.UpdateSource();

            bindingExpression = tblkText.GetBindingExpression(TextBlock.FontSizeProperty);
            bindingExpression.UpdateSource();

            bindingExpression = tblkText.GetBindingExpression(TextBlock.FontWeightProperty);
            bindingExpression.UpdateSource();

            bindingExpression = tblkText.GetBindingExpression(TextBlock.ForegroundProperty);
            bindingExpression.UpdateSource();

            //(FindResource("LabelStyle") as Style).Resources.; 
            //(FindResource("LabelStyle") as Style).;     // as Label).ref ();

            bindingExpression = Label1.GetBindingExpression(Label.StyleProperty);
            bindingExpression.UpdateSource();

            bindingExpression = btnFont.GetBindingExpression(Button.StyleProperty);
            bindingExpression.UpdateSource();

            bindingExpression = btnEmail.GetBindingExpression(Button.StyleProperty);
            bindingExpression.UpdateSource();

            bindingExpression = btnCancel.GetBindingExpression(Button.StyleProperty);
            bindingExpression.UpdateSource();

    }
}

app.xaml：

<Application x:Class="PostcardMVVM.App"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:local="clr-namespace:PostcardMVVM"
         StartupUri="MainWindow.xaml">
<Application.Resources>
    <Style x:Key="ControlStyle" TargetType="{x:Type UserControl}">
        <Setter Property="FontSize" Value="18" />
        <Setter Property="FontFamily" Value="Calibri" />
        <Setter Property="FontStyle" Value="Normal" />
    </Style>
    <Style x:Key="ButtonStyle" TargetType="{x:Type Button}">
        <Setter Property="FontSize" Value="18" />
        <Setter Property="FontFamily" Value="Calibri" />
        <Setter Property="FontStyle" Value="Normal" />
    </Style>
    <Style x:Key="LabelStyle" TargetType="{x:Type Label}">
        <Setter Property="FontSize" Value="18" />
        <Setter Property="FontFamily" Value="Calibri" />
        <Setter Property="FontStyle" Value="Normal" />
    </Style>

</Application.Resources>

正确状态下明信片表格的屏幕截图

Answer 1

这一行：

txtText.FontWeight = FontWeight = fontDialog1.Font.Bold ? FontWeights.Bold : FontWeights.Regular;

有一个额外的

FontWeight=

，它将把父窗体设置为粗体。它的子控件，包括您的按钮，将继承它的粗体。

摆脱无关的设置器应该可以解决这个问题。