Article
11/18/2011

KeyedCollection<TKey, TItem>.InsertItem Method

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Inserts an element into the KeyedCollection<TKey, TItem> at the specified index.

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

Syntax

'Declaration
Protected Overrides Sub InsertItem ( _
    index As Integer, _
    item As TItem _
)

protected override void InsertItem(
    int index,
    TItem item
)

Parameters

index
Type: System.Int32
The zero-based index at which item should be inserted.

item
Type: TItem
The object to insert.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	index is less than 0. -or- index is greater than Count.

ArgumentOutOfRangeException

index is less than 0.

-or-

index is greater than Count.

Remarks

If index is equal to Count, item is added to the end of the KeyedCollection<TKey, TItem>.

Important Note:
This method overrides the protected Collection<T>.InsertItem(Int32, T) method. The two methods are not overloads, as the overload list page states. In fact, they have exactly the same signature, because the base class of KeyedCollection<TKey, TItem> (KeyedCollection(Of TKey, TItem) in Visual Basic, generic<TKey, TItem> ref class KeyedCollection in C++) is Collection<TItem>, where the generic type parameter TItem of KeyedCollection<TKey, TItem> is substituted for the generic type parameter T of the Collection<T> generic class. The documentation build tools do not resolve these signatures correctly.

This method overrides the protected Collection<T>.InsertItem(Int32, T) method. The two methods are not overloads, as the overload list page states. In fact, they have exactly the same signature, because the base class of KeyedCollection<TKey, TItem> (KeyedCollection(Of TKey, TItem) in Visual Basic, generic<TKey, TItem> ref class KeyedCollection in C++) is Collection<TItem>, where the generic type parameter TItem of KeyedCollection<TKey, TItem> is substituted for the generic type parameter T of the Collection<T> generic class. The documentation build tools do not resolve these signatures correctly.

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

Notes for Implementers

Override this method to provide customized behavior for the Add and Insert methods, inherited from the Collection<T> generic class.

Call the base class implementation of this method to insert the item into the underlying collection and to update the lookup dictionary.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.