Insert Method

Collection.Insert Method

Inserts an element into the Collection at the specified index.

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

public void Insert (
	int index,
	T item
public final void Insert (
	int index, 
	T item
public final function Insert (
	index : int, 
	item : T
Not applicable.



The zero-based index at which item should be inserted.


The object to insert. The value can be a null reference (Nothing in Visual Basic) for reference types.

Exception typeCondition


index is less than zero.


index is greater than Count.

Collection accepts a null reference (Nothing in Visual Basic) as a valid value for reference types and allows duplicate elements.

If index is equal to Count, item is added to the end of Collection.

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

Notes to Inheritors: Derived classes can override InsertItem to change the behavior of this method.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0

.NET Compact Framework

Supported in: 2.0

XNA Framework

Supported in: 1.0

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