<Button Width="100" Height="50" Content="点击" Foreground="Red" Click="Button_Click"><Button.Template><ControlTemplate TargetType="Button"><Border Background="{TemplateBinding Background}" CornerRadius="20"><ContentPresenter VerticalAlignment="Center" HorizontalAlignment="Center"></ContentPresenter></Border></ControlTemplate></Button.Template>
ContentPresenter 是内容呈现器
1、先用Button.Template
2、再用ControlTemplate 里面写一个TargetType
3、在内容区域里要显示当前按钮的文本的话,使用 ConentPresenter