WPF 实现带标题的TextBox

这篇博客将分享在WPF中如何创建一个带Title的TextBox。首先请看一下最终的效果，

实现思路：使用TextBlock+TextBox来实现，TextBlock用来显示Title。

实现代码，

TitleTextBox

    [TemplatePart(Name = TitleTextBlockKey, Type = typeof(TextBlock))]
public class TitleTextBox : TextBox
    {
private const string TitleTextBlockKey = "PART_TitleTextBlock";

private TextBlock _tbkTitle;

public static readonly DependencyProperty TitleProperty;

public string Title
        {
get { return (string)GetValue(TitleProperty); }
set { SetValue(TitleProperty, value); }
        }

static TitleTextBox()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(TitleTextBox), new FrameworkPropertyMetadata(typeof(TitleTextBox)));

            TitleProperty = DependencyProperty.Register("Title", typeof(string), typeof(TitleTextBox), new UIPropertyMetadata(new PropertyChangedCallback(TitlePropertyChangedCallback)));
        }

private static void TitlePropertyChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            TitleTextBox ttb = d as TitleTextBox;

if (ttb._tbkTitle != null)
            {
                ttb._tbkTitle.Text = (string)e.NewValue;
            }
        }

public override void OnApplyTemplate()
        {
base.OnApplyTemplate();

            _tbkTitle = Template.FindName(TitleTextBlockKey, this) as TextBlock;
            _tbkTitle.Text = Title;
        }
    }

定义TitleTextBox样式，

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:local="clr-namespace:WPFTitleTextBox.Resources.Styles"
 xmlns:uc="clr-namespace:WPFTitleTextBox">
<Style TargetType="{x:Type uc:TitleTextBox}">
<Setter Property="SnapsToDevicePixels" Value="True"/>
<Setter Property="FontSize" Value="12"/>
<Setter Property="Height" Value="28"/>
<Setter Property="UndoLimit" Value="0"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type uc:TitleTextBox}">
<Border x:Name="OuterBorder" BorderBrush="#8b99bc" BorderThickness="1" CornerRadius="1" Background="#f7f7f7">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>

  <TextBlock x:Name="PART_TitleTextBlock" Text="{Binding Title}" Foreground="#a7abb0" VerticalAlignment="Center" Margin="5,0"/>
<Line Grid.Column="1" Stroke="#ccd1d7" StrokeDashArray="2,2" StrokeThickness="1.5" X1="0" Y1="0" 
                                  X2="0" Y2="{TemplateBinding Height}" Margin="0,4"/>

<Border Grid.Column="2" Background="White">
<ScrollViewer x:Name="PART_ContentHost" Margin="5,0" VerticalAlignment="Center" FontSize="14"/>
</Border>
</Grid>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ResourceDictionary>

在XAML中需要引用TitleTextBox。

    <Grid>
<StackPanel>
<local:TitleTextBox Title="姓名" Width="270" Margin="5,10"/>
<local:TitleTextBox Title="班级" Width="270"/>
<local:TitleTextBox Title="专业" Width="270" Margin="5,10"/>
</StackPanel>
</Grid>

使用时设置一下Title即可。使用方式和普通TextBox一样。

以后如果遇到带Title的ComboBox，CheckBox等都可以参考上面的实现思路。

感谢您的阅读，代码点击这里下载。