https://learn.microsoft.com/en-us/dotnet/api/system.windows.media.visualtreehelper.getchildrencount?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-9.0
VisualTreeHelper.GetChildrenCount(DependencyObject) Method (System.Windows.Media) | Microsoft Learn
Returns the number of children that the specified visual object contains.
windows mediamethodsystemmicrosoftlearn
https://learn.microsoft.com/ja-jp/dotnet/api/system.windows.media.visualtreehelper.getparent?view=netframework-4.8
VisualTreeHelper.GetParent(DependencyObject) Method (System.Windows.Media) | Microsoft Learn
Returns a DependencyObject value that represents the parent of the visual object.
windows mediagetparentmethodsystemmicrosoft
https://learn.microsoft.com/en-us/dotnet/api/system.windows.media.visualtreehelper.setrootdpi?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-9.0
VisualTreeHelper.SetRootDpi(Visual, DpiScale) Method (System.Windows.Media) | Microsoft Learn
Updates the DPI information of a Visual. It can only be called on a Visual without a parent.
windows mediavisualmethodsystemmicrosoft