CollectionBase.IList.Insert Method (Int32, Object)


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Inserts an element into the CollectionBase at the specified index.

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

private abstract Insert : 
        index:int *
        value:Object -> unit
private override Insert : 
        index:int *
        value:Object -> unit


Type: System.Int32

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

Type: System.Object

The Object to insert.

Exception Condition

index is less than zero.


index is greater than Count.


The CollectionBase is read-only.


The CollectionBase has a fixed size.

If Count already equals the capacity, the capacity of the list is doubled by automatically reallocating the internal array before the new element is inserted.

If index is equal to Count, value is added to the end of CollectionBase.

In collections of contiguous elements, such as lists, the elements that follow the insertion point move down to accommodate the new element. If the collection is indexed, the indexes of the elements that are moved are also updated. This behavior does not apply to collections where elements are conceptually grouped into buckets, such as a hash table.

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

Notes to Implementers:

This method calls OnValidate, OnInsert, and OnInsertComplete.

The following code example implements the CollectionBase class and uses that implementation to create a collection of Int16 objects.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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