C# | Check if an Array has fixed size or not

Last Updated : 11 Jul, 2025

Array.IsFixedSize Property is used to get a get a value indicating whether the Array has a fixed size. This property implements the IList.IsFixedSize Property . Syntax:

public bool IsFixedSize { get; }

Property Value: This property is always return true for all arrays. Below programs illustrate the use of above-discussed property: Example 1:

Output:

Topic of C#:
Array, 
String, 
Stack, 
Queue, 
Exception, 
Operators 

Result: True

Example 2:

Output:

Result: True

Note:

Array implements the IsFixedSize property because it is required by the System.Collections.IList interface.
An array with a fixed size does not allow the addition or removal of elements after the creation of an array, but modification of existing elements are allowed.
Retrieving the value of this property is an O(1) operation.

Reference:

https://learn.microsoft.com/en-us/dotnet/api/system.array.isfixedsize?view=netframework-4.7.2

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URL: https://www.geeksforgeeks.org/c-sharp/c-sharp-check-if-an-array-has-fixed-size-or-not/

⇱ C# | Check if an Array has fixed size or not - GeeksforGeeks

C# | Check if an Array has fixed size or not

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