WPF带提示的文本控件和密码控件

示例代码：狂点此处 元芳，就这么认为地。

首先来个效果图：

Password前台代码：

    <Border Background="White" Padding="2,3" Margin="1" d:LayoutOverrides="VerticalAlignment, GridBox"/>
         <TextBlock Text="请输入密码" x:Name="txtPasswordTip" Padding="7,3" Margin="1,3,1,1" FontFamily="SimSun" d:LayoutOverrides="VerticalAlignment, GridBox"/>
         <PasswordBox Padding="4,3,2,3"    Background="Transparent" x:Name="password" PasswordChanged="password_PasswordChanged" d:LayoutOverrides="GridBox" Password=""/>

Textbox 前台代码：

<TextBox      FontSize="14" Padding="2,3"  x:Name="userName"  TextChanged="userName_TextChanged" >
             
             
             <TextBox.Resources>
                 <VisualBrush x:Key="HelpBrush" TileMode="None" Opacity="1"   Stretch="None" AlignmentX="Left" >
                     <VisualBrush.Visual>
                         <Grid Background="White" Width="150" Height="26" >
                             <TextBlock FontStyle="Normal" Text="{Binding  }"  x:Name="txtblock"  Margin="1,0,0,0"  Padding="5,3,2,3" HorizontalAlignment="Left" VerticalAlignment="Center"   FontSize="12"  FontFamily="SimSun"  />
                         </Grid>
                     </VisualBrush.Visual>
                 </VisualBrush>
             </TextBox.Resources>
             <TextBox.Style>
                 <Style TargetType="{x:Type TextBox}">
                     <Style.Triggers>
                         <Trigger Property="Text" Value="{x:Null}">
                             <Setter Property="Background" Value="{StaticResource HelpBrush}"/>
                         </Trigger>
                         <Trigger Property="Text" Value="">
                                 
                             <Setter Property="Background" Value="{StaticResource HelpBrush}"/>
                         </Trigger>
                     </Style.Triggers>
                 </Style>
             </TextBox.Style>
 
         </TextBox>