NullReferenceException when closing our application

SyntaxEditor for Windows Forms Forum

Posted 17 years ago by Adam Dickinson
Version: 4.0.0246
Platform: .NET 2.0
Environment: Windows XP (32-bit)
We tripped over this exception when trying to close down our application:

System.NullReferenceException: Object reference not set to an instance of an object.
at ActiproSoftware.SyntaxEditor.Document.get_Characters(Int32 index)
at ActiproSoftware.SyntaxEditor.DisplayLineCollection.a(Int32 A_0)
at ActiproSoftware.SyntaxEditor.DisplayLine.get_Length()
at ActiproSoftware.SyntaxEditor.EditorView.GetCursor(Point point)
at ActiproSoftware.WinUICore.UIControl.OnMouseMove(MouseEventArgs e)
ActiproSoftware.SyntaxEditor.SyntaxEditor.OnMouseMove(MouseEventArgs e)
at System.Windows.Forms.Control.WmMouseMove(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at ActiproSoftware.SyntaxEditor.SyntaxEditor.WndProc(Message& m)
System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message&
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

I don't believe there were any syntax errors or Intellisense popups of any kind showing. Not sure how to reproduce it. Sorry :(

Comments (3)

Posted 17 years ago by Actipro Software Support - Cleveland, OH, USA
Hi Adam,

Without a repro, it's hard to say how that is happening unless the Control is already disposed and still getting mouse input? If you can, please try and figure out how to duplicate it in a small sample project that we could debug. Thanks.

Actipro Software Support

Posted 17 years ago by shark92651
I am seeing this error as well. In my case, it happens when the mouse is over the control while it is being disposed.
Posted 17 years ago by Actipro Software Support - Cleveland, OH, USA
Please try with our latest maintenance release and if you still see it there, put together a small sample project that shows it happening and email that over so we can debug it. Thanks!

Actipro Software Support

The latest build of this product (v24.1.0) was released 3 months ago, which was after the last post in this thread.

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