C# | Check if ListDictionary has a fixed size

Last Updated : 11 Jul, 2025

ListDictionary.IsFixedSize property is used to get a value indicating whether the ListDictionary has a fixed size or not. Syntax:

public bool IsFixedSize { get; }

Return Value : This property always returns false. Example:

CSHARP

// C# code to check if ListDictionary
// has a fixed size
using System;
using System.Collections;
using System.Collections.Specialized;

class GFG {

    // Driver code
    public static void Main()
    {

        // Creating a ListDictionary named myDict
        ListDictionary myDict = new ListDictionary();

        myDict.Add("Australia", "Canberra");
        myDict.Add("Belgium", "Brussels");
        myDict.Add("Netherlands", "Amsterdam");
        myDict.Add("China", "Beijing");
        myDict.Add("Russia", "Moscow");
        myDict.Add("India", "New Delhi");

        // Checking if ListDictionary has a fixed size
        Console.WriteLine(myDict.IsFixedSize);
    }
}

Output:

False

Note:

A collection with a fixed size does not allow the addition or removal of elements after the collection is created, but it allows the modification of existing elements.
A collection with a fixed size is simply a collection with a wrapper that prevents adding and removing elements. Therefore, if changes are made to the underlying collection, including the addition or removal of elements, the fixed-size collection reflects those changes.
Retrieving the value of this property is an O(1) operation.

Reference: