C# | Get or set the element at specified index in Collection<T> Last Updated : 01 Feb, 2019 Summarize Comments Improve Suggest changes Share Like Article Like Report Collection<T>.Item[Int32] property is used to get or set the element at the specified index. Syntax: public T this[int index] { get; set; } Here, index is the zero-based index of the element to get or set. Return Value: The element at the specified index. Exception: This method will give ArgumentOutOfRangeException if the index is less than zero or index is equal to or greater than Count. Below given are some examples to understand the implementation in a better way: Example 1: CSHARP // C# code to get or set the // element at the specified index using System; using System.Collections.Generic; using System.Collections.ObjectModel; class GFG { // Driver code public static void Main() { // Creating a collection of strings Collection<string> myColl = new Collection<string>(); // Adding elements in Collection myColl myColl.Add("A"); myColl.Add("B"); myColl.Add("C"); myColl.Add("D"); myColl.Add("E"); // Displaying the elements in myColl foreach(string str in myColl) { Console.WriteLine(str); } // Get the element at index 2 Console.WriteLine("Element at index 2 is : " + myColl[2]); // Get the element at index 3 Console.WriteLine("Element at index 3 is : " + myColl[3]); // Set the element at index 3 myColl[3] = "GFG"; // Displaying the elements in myColl foreach(string str in myColl) { Console.WriteLine(str); } } } Output: A B C D E Element at index 2 is : C Element at index 3 is : D A B C GFG E Example 2: CSHARP // C# code to get or set the // element at the specified index using System; using System.Collections.Generic; using System.Collections.ObjectModel; class GFG { // Driver code public static void Main() { // Creating a collection of ints Collection<int> myColl = new Collection<int>(); // Adding elements in Collection myColl myColl.Add(2); myColl.Add(3); myColl.Add(4); myColl.Add(5); // Displaying the elements in myColl foreach(int i in myColl) { Console.WriteLine(i); } // Get the element at index -1 // This should raise "ArgumentOutOfRangeException" // as the index is less than 0 Console.WriteLine("Element at index -1 is : " + myColl[-1]); // Set the element at index 2 myColl[2] = 10; // Displaying the elements in myColl foreach(int i in myColl) { Console.WriteLine(i); } } } Runtime Error: Unhandled Exception: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index Note: Collection<T> accepts null as a valid value for reference types and allows duplicate elements. This property provides the ability to access a specific element in the collection by using the syntax : myCollection[index]. Retrieving the value of this property is an O(1) operation. Setting the property is also an O(1) operation. Reference: https://docs.microsoft.com/en-us/dotnet/api/system.collections.objectmodel.collection-1.item?view=netframework-4.7.2 Comment More infoAdvertise with us Next Article C# | Get or set the element at specified index in Collection<T> S Sahil_Bansall Follow Improve Article Tags : C# CSharp-Collections.ObjectModel-Namespace CSharp-Collection-Class Similar Reads C# | Remove element at specified index of Collection<T> Collection<T>.RemoveAt(Int32) is used to remove the element at the specified index of the Collection<T>. Syntax: public void RemoveAt (int index); Here, index is the zero-based index of the element to remove. Exception: This method will give ArgumentOutOfRangeException if the index is le 2 min read C# | Gets or Sets the element at the specified index in the List List<T>.Item[Int32] Property is used to gets or sets the element at the specified index. Properties of List: It is different from the arrays. A list can be resized dynamically but arrays cannot. List class can accept null as a valid value for reference types and it also allows duplicate elemen 2 min read C# | Insert an element into Collection<T> at specified index Collection<T>.Insert(Int32, T) method is used to insert an element into the Collection<T> at the specified index. Syntax: public void Insert (int index, T item); Parameters: index : The zero-based index at which item should be inserted. item : The object to insert. 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