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Collection<T>.IList.IndexOf Method

Determines the index of a specific item in the IList.

Namespace:  System.Collections.ObjectModel
Assembly:  mscorlib (in mscorlib.dll)

int IList.IndexOf(
	Object value
)

Parameters

value
Type: System.Object

The Object to locate in the IList.

Return Value

Type: System.Int32
The index of value if found in the list; otherwise, -1.

Implements

IList.IndexOf(Object)

ExceptionCondition
ArgumentException

value is of a type that is not assignable to the IList.

This method determines equality using the default comparer Comparer<T>.Default. Comparer<T>.Default checks whether type T implements System.IComparable<T> and uses that implementation, if available. If not, Comparer<T>.Default checks whether type T implements System.IComparable. If type T does not implement either interface, this method uses Object.Equals.

This method is an O(n) operation, where n is Count.

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, Xbox 360, Zune

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

.NET Compact Framework

Supported in: 3.5, 2.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
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