IndexOf Method

ListBox.SelectedIndexCollection.IndexOf Method

Returns the index within the ListBox.SelectedIndexCollection of the specified index from the ListBox.ObjectCollection of the ListBox.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public int IndexOf(
	int selectedIndex


Type: System.Int32

The zero-based index from the ListBox.ObjectCollection to locate in this collection.

Return Value

Type: System.Int32
The zero-based index in the collection where the specified index of the ListBox.ObjectCollection was located within the ListBox.SelectedIndexCollection; otherwise, negative one (-1).

Once you know that an item is located within the collection (using the Contains method), you can use the IndexOf method to determine where a specific index position within the ListBox.ObjectCollection for the ListBox is stored within the ListBox.SelectedIndexCollection.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

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