Returns the index within the collection of the specified item.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
- Type: System.Object
An object representing the item to locate in the collection.
Return ValueType: System.Int32
The zero-based index where the item is located within the collection; otherwise, negative one (-1).
The method enables you to determine where an item is located within the collection. To determine whether an item is located within the collection before calling this method, use the Contains method.
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.