WPF TextBox MaxLength 属性在应用某些样式后不起作用

Question

I have an issue in my C# code. Could you please help me? I have a textbox with such XAML code:

<TextBox 
        Margin="0,10" 
        x:Name="SomeName"
        TextAlignment="Center"
        FontWeight="Bold"
        Focusable="True"
        MaxLength="100"
        Width="200"
        Style="{StaticResource SomeStyle}"
        Text="{Binding PropName, UpdateSourceTrigger=PropertyChanged}" />

UPDATE

Here is my SomeStyle code:

    <Style x:Key="SomeStyle" TargetType="{x:Type TextBox}" >
    <Setter Property="Focusable" Value="False" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type TextBox}">
                <Border BorderBrush="{TemplateBinding BorderBrush}" 
                        Background="{TemplateBinding Background}" >
                    <Grid ClipToBounds="True" >
                        <TextBox Text="{Binding Path=Text, RelativeSource={RelativeSource TemplatedParent}, 
                                                Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                                 Panel.ZIndex="2" />

                        <TextBox Text="{TemplateBinding Tag}" Background="{TemplateBinding Background}" Panel.ZIndex="1">
                            <TextBox.Style>
                                <Style TargetType="{x:Type TextBox}">
                                    <Setter Property="FontStyle" Value="Italic" />
                                    <Setter Property="BorderThickness" Value="0" />
                                    <Style.Triggers>
                                        <DataTrigger Binding="{Binding Path=Text, Source={x:Reference textSource}}" Value="">
                                        </DataTrigger>
                                        <Trigger Property="IsMouseOver" Value="True">
                                            <Setter Property="BorderThickness" Value="0" />
                                            <Setter Property="BorderBrush" Value="Transparent" />
                                        </Trigger>
                                    </Style.Triggers>
                                </Style>
                            </TextBox.Style>
                        </TextBox>
                    </Grid>
                </Border>
                <ControlTemplate.Triggers>
                    <Trigger Property="IsMouseOver" Value="True">
                        <!--<Setter Property="BorderBrush" Value="Transparent" />-->
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

If I remove a Style prop, the MaxLength prop work properly. This referenced style does not contain a constraint for MaxLength. Any ideas?

Answer 1

You have others TextBoxes in your TextBox Control Template and you don't pass them MaxLength value, so it doesn't work. What you are trying to do with this template?