The GridSplitter control redistributes space between rows or columns in a Grid, without changing the dimensions of the Grid. For example, when a GridSplitter resizes two columns, the ActualWidth property of one column is increased while at the same time the ActualWidth property of the other column is decreased by the same amount.
The following table shows how to define a horizontal or vertical GridSplitter by setting the HorizontalAlignment and VerticalAlignment properties and by leaving the ResizeDirection and ResizeBehavior properties set to their default values.
How to create vertical and horizontal GridSplitter controls
A GridSplitter can overlap a row or column that contains other content, or it can occupy a row or column by itself. For more information about how to define a GridSplitter, see How to: Resize Rows with a GridSplitter and How to: Resize Columns with a GridSplitter.
If the HorizontalAlignment and VerticalAlignment property settings do not achieve the desired GridSplitter behavior, you can change the ResizeDirection and ResizeBehavior property settings.
A GridSplitter may be obscured by other objects that are contained in the Children collection of the Grid. For information about how to prevent this situation, see How to: Make Sure That a GridSplitter Is Visible.
Dependency properties for this control might be set by the control’s default style. If a property is set by a default style, the property might change from its default value when the control appears in the application. The default style is determined by which desktop theme is used when the application is running. For more information, see Themes.