VScroll may only be set when the object is created with ⎕WC and may not subsequently be changed with ⎕WS or assignment.

For a Form object, the value ¯1 specifies that the Form has a vertical scrollbar. A value of 0 (which is the default) means that it does not.

When applied to an Edit object, the value ¯2 specifies that the data is scrollable vertically, but only by using the cursor keys; a scrollbar is not provided. A value of ¯1 causes a scrollbar to be displayed (whether or not one is needed).

When applied to a List object, the value ¯2 specifies that the data is scrollable vertically, but only by using the cursor keys; a scrollbar is not provided. A value of ¯1 causes a scrollbar to be displayed if required (when the list of items exceeds the height of the object).

When applied to a Combo or ComboEx object, a value of ¯1 or ¯2 causes a scrollbar to be displayed, whether or not one is required.

For all these objects, a value of 0 inhibits scrolling altogether.

For a Scroll object, VScroll may be ¯1 or 0. If it is ¯1 the direction of the scrollbar is vertical. If both HScroll and VScroll are set to ¯1, HScroll takes precedence and forces VScroll back to 0.

For a StatusBar, TabBar or ToolBar with Align set to Left or Right, VScroll determines whether or not a vertical scrollbar is provided and how the object positions its children. If VScroll is 0 (the default) the object organises its children in multiple columns and does not provide a scrollbar. If VScroll is ¯1 or ¯2, the object organises its children in a single column and provides a mini scrollbar to allow those positioned beyond the bottom edge of the object to be scrolled into view. If VScroll is ¯1, the scrollbar is always shown. If VScroll is ¯2, it is only shown when needed.

For a Grid, VScroll may be 0 (no vertical scrollbar), ¯1 (scrollbar is displayed when required), ¯2 (same as ¯1) or ¯3 (scrollbar is always displayed).