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List<T>.IList.IsReadOnly Property

Gets a value indicating whether the IList is read-only.

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

bool IList.IsReadOnly { get; }

Property Value

Type: System.Boolean
true if the IList is read-only; otherwise, false. In the default implementation of List<T>, this property always returns false.



A collection that is read-only does not allow the addition, removal, or modification of elements after the collection is created.

A collection that is read-only is simply a collection with a wrapper that prevents modifying the collection; therefore, if changes are made to the underlying collection, the read-only collection reflects those changes.

Retrieving the value of this property is an O(1) operation.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
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