The multiSelectRectangle property (string) determines the rectangle event selection mode. When the rectangle selection mode is enabled it lets users select multiple scheduler events using drag and drop (while holding the Shift key).
See also Event Multi-Selecting in the documentation.
"Disabled"
dp.multiSelectRectangle = "Free";
Event calendar/scheduling AJAX components. Available for JavaScript/HTML5/jQuery, ASP.NET, ASP.NET MVC. Build resource booking, project management, time tracking applications, personal and shared event calendars.