WPF中Slider 的Thumb.DragStarted 和Thumb.DragCompleted事件的应用

代码如下：

<Grid>
        <Grid.RowDefinitions>
            "*"/>
            "*"/>
            "*"/>
        Grid.RowDefinitions>
        <Slider Name="mySlider" ValueChanged="mySlider_ValueChanged" Thumb.DragStarted ="mySlider_DragStarted"
                Thumb.DragCompleted ="mySlider_DragCompleted"/>
        <TextBox Name="tboxValue" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" Text="0"
                 Grid.Row="1"/>
        <Button Content="Add" Name="btnAdd" Click="btnAdd_Click" Grid.Row="2"/>
    Grid>

private bool isdragging = false;

        private void btnAdd_Click(object sender, RoutedEventArgs e)
        {
            mySlider.Value += 1;
        }

        private void mySlider_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
        {
            if (isdragging)
                tboxValue.Text = mySlider.Value.ToString();
        }

        private void mySlider_DragStarted(object sender, System.Windows.Controls.Primitives.DragStartedEventArgs e)
        {
            isdragging = true;
        }

        private void mySlider_DragCompleted(object sender, System.Windows.Controls.Primitives.DragCompletedEventArgs e)
        {
            isdragging = false;
        }

实现了一个简单的功能。

利用一个Textbox来显示Slider的值，但是值仅在拖拽Slider的时候更新，在其他情况下改变Slider的值的时候Textbox的内容不发生变化。