C# | Get an ICollection containing keys in OrderedDictionary

Last Updated : 01 Feb, 2019

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:

// 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:

// 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]); 
        } 
    } 
} 