Assembly: System.Configuration (in system.configuration.dll)
Property Valuetrue if an attempt to add a duplicate ConfigurationElement to this ConfigurationElementCollection will cause an exception to be thrown; otherwise, false.
Note that elements with identical keys and values are not considered duplicates, and are accepted silently. Only elements with identical keys but different values are considered duplicates. For more information, see the Remarks section for the BaseAdd method.
Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.