C# | Remove all elements from the ArrayList Last Updated : 01 Feb, 2019 Comments Improve Suggest changes Like Article Like Report ArrayList represents an ordered collection of an object that can be indexed individually. It is basically an alternative to an array. It also allows dynamic memory allocation, adding, searching and sorting items in the list. ArrayList.Clear method is used to remove all the elements from the ArrayList. Properties: Elements can be added or removed from the Array List collection at any point in time. The ArrayList is not guaranteed to be sorted. The capacity of an ArrayList is the number of elements the ArrayList can hold. Elements in this collection can be accessed using an integer index. Indexes in this collection are zero-based. It also allows duplicate elements. Using multidimensional arrays as elements in an ArrayList collection is not supported. Syntax: public virtual void Clear (); Exceptions: This method will give NotSupportedException if the ArrayList is read-only or the ArrayList has a fixed size. Note: This method is an O(n) operation, where n is Count. Count is set to zero, and references to other objects from elements of the collection are also released. Capacity remains unchanged. Below programs illustrate the use of ArrayList.Clear Method: Example 1 : CSHARP // C# code to remove all elements // from an ArrayList using System; using System.Collections; class GFG { // Driver code public static void Main() { // Creating an ArrayList ArrayList myList = new ArrayList(10); // Adding elements to ArrayList myList.Add("A"); myList.Add("B"); myList.Add("C"); myList.Add("D"); myList.Add("E"); myList.Add("F"); // Displaying the elements in ArrayList Console.WriteLine("Number of elements in ArrayList initially : " + myList.Count); // Removing all elements from ArrayList myList.Clear(); // Displaying the elements in ArrayList // after Removing all the elements Console.WriteLine("Number of elements in ArrayList : " + myList.Count); } } Output: Number of elements in ArrayList initially : 6 Number of elements in ArrayList : 0 Example 2: CSHARP // C# code to remove all elements // from an ArrayList using System; using System.Collections; class GFG { // Driver code public static void Main() { // Creating an ArrayList ArrayList myList = new ArrayList(10); // Adding elements to ArrayList myList.Add(3); myList.Add(5); myList.Add(7); myList.Add(9); myList.Add(11); // Displaying the elements in ArrayList Console.WriteLine("Number of elements in ArrayList initially : " + myList.Count); // Removing all elements from ArrayList myList.Clear(); // Displaying the elements in ArrayList // after Removing all the elements Console.WriteLine("Number of elements in ArrayList : " + myList.Count); } } Output: Number of elements in ArrayList initially : 5 Number of elements in ArrayList : 0 Reference: https://docs.microsoft.com/en-us/dotnet/api/system.collections.arraylist.clear?view=netframework-4.7.2 Comment More infoAdvertise with us Next Article C# | Remove all elements from the ArrayList S Sahil_Bansall Follow Improve Article Tags : Misc C# CSharp-method CSharp-Collections-Namespace CSharp-Collections-ArrayList +1 More Practice Tags : Misc Similar Reads C# | Remove a range of elements from the ArrayList ArrayList represents an ordered collection of an object that can be indexed individually. 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