C# | Get an ICollection containing keys in OrderedDictionary Last Updated : 11 Jul, 2025 Comments Improve Suggest changes Like Article Like Report OrderedDictionary.Keys property is used to get an ICollection object containing the keys in the OrderedDictionary collection. Syntax: public System.Collections.ICollection Keys { get; } Return Value: It returns an ICollection object containing the keys in the OrderedDictionary collection. Below given are some examples to understand the implementation in a better way: Example 1: CSHARP // C# code to get an ICollection // containing the keys in OrderedDictionary using System; using System.Collections; using System.Collections.Specialized; class GFG { // Driver method public static void Main() { // Creating a orderedDictionary named myDict OrderedDictionary myDict = new OrderedDictionary(); // Adding key and value in myDict myDict.Add("key1", "value1"); myDict.Add("key2", "value2"); myDict.Add("key3", "value3"); myDict.Add("key4", "value4"); myDict.Add("key5", "value5"); // Getting an ICollection containing // the keys in OrderedDictionary ICollection keyCollection = myDict.Keys; // Creating a String array String[] myKeys = new String[myDict.Count]; // Copying the OrderedDictionary elements to // a one-dimensional Array object at the // specified index. keyCollection.CopyTo(myKeys, 0); for (int i = 0; i < myDict.Count; i++) { Console.WriteLine(myKeys[i]); } } } Output: key1 key2 key3 key4 key5 Example 2: CSHARP // C# code to get an ICollection // containing the keys in OrderedDictionary using System; using System.Collections; using System.Collections.Specialized; class GFG { // Driver method public static void Main() { // Creating a orderedDictionary named myDict OrderedDictionary myDict = new OrderedDictionary(); // Adding key and value in myDict myDict.Add("A", "Apple"); myDict.Add("B", "Banana"); myDict.Add("C", "Cat"); myDict.Add("D", "Dog"); // Getting an ICollection containing // the keys in OrderedDictionary ICollection keyCollection = myDict.Keys; // Creating a String array String[] myKeys = new String[myDict.Count]; // Copying the OrderedDictionary elements to // a one-dimensional Array object at the // specified index. keyCollection.CopyTo(myKeys, 0); for (int i = 0; i < myDict.Count; i++) { Console.WriteLine(myKeys[i]); } } } Output: A B C D Reference: https://learn.microsoft.com/en-us/dotnet/api/system.collections.specialized.ordereddictionary.keys?view=netframework-4.7.2 Comment More infoAdvertise with us Next Article Introduction to .NET Framework S Sahil_Bansall Follow Improve Article Tags : C# CSharp-Specialized-Namespace CSharp-Specialized-OrderedDictionary Similar Reads IntroductionC# TutorialC# (pronounced "C-sharp") is a modern, versatile, object-oriented programming language developed by Microsoft in 2000 that runs on the .NET Framework. 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C# has multiple indexers in a single class. To overload an indexer, declare it with multiple parameters an 3 min read Like