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ICollection(T).Remove Method

Removes the first occurrence of a specific object from the ICollection(T).

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

abstract Remove : 
        item:'T -> bool 


Type: T
The object to remove from the ICollection(T).

Return Value

Type: System.Boolean
true if item was successfully removed from the ICollection(T); otherwise, false. This method also returns false if item is not found in the original ICollection(T).


The ICollection(T) is read-only.

Implementations can vary in how they determine equality of objects; for example, List(T) uses Comparer(T).Default, whereas, Dictionary(TKey, TValue) allows the user to specify the IComparer(T) implementation to use for comparing keys.

In collections of contiguous elements, such as lists, the elements that follow the removed element move up to occupy the vacated spot. 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.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.