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

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

bool IsReadOnly { get; }
property bool IsReadOnly {
	bool get();
abstract IsReadOnly : bool with get
ReadOnly Property IsReadOnly As Boolean

Property Value


true if the ICollection is read-only; otherwise, false.

A collection that is read-only does not allow the addition or removal of elements after the collection is created. Note that read-only in this context does not indicate whether individual elements of the collection can be modified, since the ICollection interface only supports addition and removal operations. For example, the property of an array that is cast or converted to an ICollection object returns true, even though individual array elements can be modified.

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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