Command="{Binding ConfirmRegisterCommand}" CommandParameter="{Binding RelativeSource={x:Static RelativeSource.Self},Path=DataContext}"

一.FindAncestor

有时候我们不确定作为数据源的对象叫什么名字,但知道作为绑定源与UI布局有相对的关系,如下是一段XAML代码,说明多层布局控件中放置一个文本控件,来显示父级控件的名称。
1、XAML
Html代码:
 <Grid x:Name="g1" Background="Red" Margin="10">
        <DockPanel x:Name="d1" Background="Orange" Margin="10">
            <Grid x:Name="g2" Background="Yellow" Margin="10">
                <DockPanel x:Name="d2" Background="LawnGreen" Margin="10">
                    <TextBox x:Name="textBox1" FontSize="24" Margin="10"/>
                </DockPanel>
            </Grid>
        </DockPanel>
    </Grid>

2、后台代码
Csharp代码 :
 RelativeSource rs = new RelativeSource(RelativeSourceMode.FindAncestor);
//设定为离自己控件最近的第二层父控件
 rs.AncestorLevel = 2;
//设定父控件为Gird类型
 rs.AncestorType = typeof(Grid);
//绑定源为Grid的名称
 Binding binding = new Binding("Name") { RelativeSource=rs};
//将绑定的源放在文本显示内容中
 this.textBox1.SetBinding(TextBox.TextProperty, binding);

3、以上后台代码等同于XAML中的
Html代码:
 <TextBox x:Name="textBox1" FontSize="24" Margin="10" Text="{Binding RelativeSource={RelativeSource FindAncestor,AncestorType={x:Type Grid},AncestorLevel=2},Path=Name}"/>

二.TemplatedParent
TemplatedParent是RelativeSource的其中一种方式,使用该方式将使源元素成为模板目标类型—即TargetType;如果该绑定是在模板中,那么它的作为范围也只限于该模板.
例:
<Style TargetType="{x:Type local:TemplatedParent}">
        <Setter Property="Background" Value="Green"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type local:TemplatedParent}">
                    <Grid>
                        <Ellipse>
                            <Ellipse.Fill>
                                <SolidColorBrush Color="{Binding Path=Background.Color,RelativeSource={RelativeSource TemplatedParent}}"/>
                           </Ellipse.Fill>
                        </Ellipse>
                    </Grid>
                </ControlTemplate>
           </Setter.Value>
        </Setter>
    </Style>
这样绑定的源元素就指向local:TemplatedParent这个目标类型了,所以当你修改目标类型的背景颜色时,Ellipse也将跟随它变化。

三.Self
<Window x:Class="WpfApplication1.chap5_2"
 xmlns="​​http://schemas.microsoft.com/winfx/2006/xaml/presentation​​​"
 xmlns:x="​​http://schemas.microsoft.com/winfx/2006/xaml​​​"
 Title="chap5_2" Height="300" Width="300">
    <Grid>
           <Slider Name="slider"
              Margin="4" Interval="1"
             TickFrequency="1"
             IsSnapToTickEnabled="True"
            Minimum="0" Maximum="100"
       ToolTip="{Binding RelativeSource ={ RelativeSource Self}, Path=Value}"/>
    </Grid>
</Window>
其中Binding RelativeSource={RelativeSource Self}等价于Binding RelativeSource={x:Static RelativeSource.Self}