Returns the index at which the specified item is located.
Assembly: PresentationFramework (in PresentationFramework.dll)
If this method returns an index other than -1, it must always be true that view[index-1] < item <= view[index], where the comparisons are done using the IComparer.Compare method of the view, if one exists.
This particular behavior of the method is used by some CollectionChanged event handlers to speed up reaction to insertion and deletion. If the derived class does not override this method, a listener does a binary search using the IComparer.Compare method.
Windows Phone 8.1, Windows Phone 8, 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.