The DialogResult can be used from the code that showed a modal RadWindow to determine whether a user accepted or canceled it. In other words this property returns the user input into the modal DialogResult which does not correspond to whether the RadWindow is Closed or Opened.
To open or close a RadWindow we should call the Show() and Close() methods. I suggest referring to this article
for information on how to Close a RadWindow through its content.
Hopefully this helps.
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