Panning with Arrow keys crashes MO1.2/MOPlus LabelPlacer project

Last Published: April 25, 2020


If an arrow key or the PageUp/PageDown key is pressed while a redraw of a map is in progress, the application will crash if it uses the LabelPlacer object.


Using the arrow keys to pan will cancel a redraw of the map that is in progress. This appears to cause an exception in MOPlus.DLL.

Solution or Workaround

Set the CancelAction property to moCancelNone when the form with the map is loaded:

Map1.CancelAction = moCancelNone

Article ID:000002700

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