IndexOf Method

ComboBox.ObjectCollection.IndexOf Method

Retrieves the index within the collection of the specified item.

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

public int IndexOf(
	Object value


Type: System.Object

An object representing the item to locate in the collection.

Return Value

Type: System.Int32
The zero-based index where the item is located within the collection; otherwise, -1.




The value parameter was null.

The IndexOf method enables you to determine where an item is located within the collection. To determine if an item is located within the collection before calling this method, use the Contains method.

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, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

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

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

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