If the WidthAutoResize property is True, the column's width is resized after user edits the cell. Also, the column's width is refreshed if the user adds new items to the control. If the WidthAutoResize property is True, the column's width is not larger than MaxWidthAutoResize value, and it is not less than MinWidthAutoResize value. You can use the AutoWidth property to computes the column's width to fit its content. For instance, if you have a tree with one column, and this property True, you can simulate a simple tree, because the control will automatically add a horizontal scroll bar when required. Use the ColumnAutoResize property to specify whether the control resizes the visible columns so they fit the control's client area. If the WidthAutoResize property is True, the user is not able to resize the column, so the AllowSizing property has no effect in this case.