Question

我需要TextBox的占位符，并找到了这个有用的代码：

<Style x:Key="placeHolder" TargetType="{x:Type TextBox}">   
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type TextBox}">
                    <Grid>
                        <TextBox Text="{Binding Path=Text,
                                            RelativeSource={RelativeSource TemplatedParent}, 
                                            Mode=TwoWay,
                                            UpdateSourceTrigger=PropertyChanged}"
                             x:Name="textSource" 
                             Background="Transparent" 
                             Panel.ZIndex="2" 
                                 BorderThickness="0,0,0,1"/>
                        <TextBox Text="{TemplateBinding Tag}" Background="{TemplateBinding Background}" Panel.ZIndex="1">
                            <TextBox.Style>
                                <Style TargetType="{x:Type TextBox}">
                                    <Setter Property="Foreground" Value="Transparent"/>
                                    <Style.Triggers>
                                        <DataTrigger Binding="{Binding Path=Text, Source={x:Reference textSource}}" Value="">
                                            <Setter Property="Foreground" Value="LightGray"/>
                                        </DataTrigger>
                                    </Style.Triggers>
                                </Style>
                            </TextBox.Style>
                        </TextBox>
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

这是我的TextBox：

<TextBox x:Name="isci_tb" HorizontalAlignment="Left" Height="25" Margin="0,0,0,0" TextWrapping="Wrap"
          VerticalAlignment="Center" Width="120" BorderThickness="0, 0, 0, 1" TextChanged="isci_tb_TextChanged" Tag="išči" Style="{StaticResource placeHolder}">
            <TextBox.Background>
                <ImageBrush/>
            </TextBox.Background>
        </TextBox>

由于我是XAML的新手，因此我看不到按钮边框的位置或内容。我希望只有底部边框，而是显示所有4个边框。

Answer 1

将模板中内部TextBox的BorderThickness属性设置为0：

<Style x:Key="placeHolder" TargetType="{x:Type TextBox}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type TextBox}">
                <Grid>
                    <TextBox Text="{Binding Path=Text,
                                            RelativeSource={RelativeSource TemplatedParent}, 
                                            Mode=TwoWay,
                                            UpdateSourceTrigger=PropertyChanged}"
                             x:Name="textSource" 
                             Background="Transparent" 
                             Panel.ZIndex="2" 
                                 BorderThickness="0,0,0,1"/>
                    <TextBox Text="{TemplateBinding Tag}" Background="{TemplateBinding Background}" Panel.ZIndex="1"
                                     BorderThickness="0">
                        <TextBox.Style>
                            <Style TargetType="{x:Type TextBox}">
                                <Setter Property="Foreground" Value="Transparent"/>
                                <Style.Triggers>
                                    <DataTrigger Binding="{Binding Path=Text, Source={x:Reference textSource}}" Value="">
                                        <Setter Property="Foreground" Value="LightGray"/>
                                    </DataTrigger>
                                </Style.Triggers>
                            </Style>
                        </TextBox.Style>
                    </TextBox>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

StaticResource改变TextBox的边框

1 个答案: