Determines if the specified item is located within the collection.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
The method enables you to determine if an object is a member of the collection. Once you know that the item is located within the collection, you can use the IndexOf method to determine where the item is located within the collection.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.