Open In App

C# | Get an ICollection containing the keys in HybridDictionary

Improve
Improve
Like Article
Like
Save
Share
Report

HybridDictionary.Keys property is used to get an ICollection containing the keys in the HybridDictionary.

Syntax:

public System.Collections.ICollection Keys { get; }

Return Value: It returns an ICollection containing the keys in the HybridDictionary.

Below programs illustrate the use of HybridDictionary.Keys Property:

Example 1:




// C# code to get an ICollection containing
// the keys in the HybridDictionary.
using System;
using System.Collections;
using System.Collections.Specialized;
  
class GFG {
  
    // Driver code
    public static void Main()
    {
  
        // Creating a HybridDictionary named myDict
        HybridDictionary myDict = new HybridDictionary();
  
        // Adding key/value pairs in myDict
        myDict.Add("A", "Apple");
        myDict.Add("B", "Banana");
        myDict.Add("C", "Cat");
        myDict.Add("D", "Dog");
        myDict.Add("E", "Elephant");
        myDict.Add("F", "Fish");
  
        // Creating a String arr named myArr
        String[] myArr = new String[myDict.Count];
  
        // copying the Keys in HybridDictionary
        // to a one-dimensional Array instance
        // at the specified index.
        myDict.Keys.CopyTo(myArr, 0);
  
        // To get an ICollection containing
        // the keys in the HybridDictionary
        for (int i = 0; i < myDict.Count; i++)
            Console.WriteLine(myArr[i]);
    }
}


Output:

A
B
C
D
E
F

Example 2:




// C# code to get an ICollection containing
// the keys in the HybridDictionary.
using System;
using System.Collections;
using System.Collections.Specialized;
  
class GFG {
  
    // Driver code
    public static void Main()
    {
  
        // Creating a HybridDictionary named myDict
        HybridDictionary myDict = new HybridDictionary();
  
        // Adding key/value pairs in myDict
        myDict.Add("I", "first");
        myDict.Add("II", "second");
        myDict.Add("III", "third");
        myDict.Add("IV", "fourth");
        myDict.Add("V", "fifth");
  
        // Creating a String arr named myArr
        String[] myArr = new String[myDict.Count];
  
        // copying the Keys in HybridDictionary
        // to a one-dimensional Array instance
        // at the specified index.
        myDict.Keys.CopyTo(myArr, 0);
  
        // To get an ICollection containing
        // the keys in the HybridDictionary
        for (int i = 0; i < myDict.Count; i++)
            Console.WriteLine(myArr[i]);
    }
}


Output:

I
II
III
IV
V

Note:

  • The order of the values in the ICollection is unspecified, but it is the same order as the associated values in the ICollection returned by the Values method.
  • The returned ICollection is not a static copy. Instead, the ICollection refers back to the keys in the original HybridDictionary. Therefore, changes to the HybridDictionary continue to be reflected in the ICollection.
  • Retrieving the value of this property is an O(1) operation.

Reference:



Last Updated : 01 Feb, 2019
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads