Sorteddictionary.Keys Property In C#

A dictionary in C# is a data structure that consists of key-value pairs, enabling efficient retrieval of values based on specific keys. The Dictionary<TKey, TValue> class in C# is an integral component of the .NET Framework and is commonly employed for constructing dictionaries.

The SortedDictionary<TKey, TValue> represents a sorted collection of key-value pairs. Accessing the Keys property of SortedDictionary<TKey, TValue> provides a structured set that represents the keys within the dictionary.

Syntax:

It has the following Syntax:

Example


public System.Collections.Generic.SortedDictionary<TKeys, TValues>.KeyCollection Keys { get; }

Return Value:

It reruns the collection of keys.

Key characteristics include:

✅ Arranged Sequence: The Keys property provides the keys in the dictionary in the sequence they were added, or following the specified custom comparer during the creation of the SortedDictionary.
✅ Immutable Key Collection: The KeyCollection generated by Keys is immutable, preventing direct alteration of its elements.

Complexity and performance:

✅ Access Complexity: The Keys property provides a direct reference to the organized collection of keys. Hence, it represents an O(1) oepration.
✅ Iterating difficulty: It iterating through a KeyCollection has an O(n) difficulty because it requires traversal of all keys.

Considerations as well as Use Cases:

✅ Key Retrieval: When you only require the keys from the SortedDictionary , the Keys property makes it simple to find them.
✅ It is handy for iterating over keys while doing operations on the dictionary's related values.

Best Practices and Considerations:

✅ Immutable Collection: Changes made to the original SortedDictionary have no impact on the KeyCollection because it is an immutable collection.
✅ Changes Should Be Avoided: Because the KeyCollection is meant to be read-only, altering the keys within it may result in exceptions.

Altering the KeyCollection (adding or deleting keys) will lead to a NotSupportedException being thrown.

Example 1:

Let's consider an example to demonstrate how to implement the dictionary functionality in C#.

Example


using System; 
using System.Collections.Generic; 

class Dic{ 


	public static void Main() 
	{ 

		// Create a new dictionary which consists of string keys
		SortedDictionary<string, string> myD = 
		new SortedDictionary<string, string>(); 

		//The key and value pairs are added to the dictionary
		myD.Add("Oman", "Muscat"); 
		myD.Add("Belgium", "Brussels"); 
		myD.Add("Germany", "Berlin"); 
		myD.Add("China", "Beijing"); 
		myD.Add("France", "Paris"); 
		myD.Add("Spain", "Madrid"); 

		// to find the count of the keys
		Console.WriteLine("The total number of key/value pairs"
			+ " in myD are : " + myD.Count); 

		//For getting only the keys, make use of the Keys property. 
		SortedDictionary<string, string>.KeyCollection keyColls = 
													myD.Keys; 

		//The KeyCollection components are strongly typed using the type // that was defined for dictionary // keys. 
		foreach(string str in keyColls) 
		{ 
			Console.WriteLine("Key = {0}", str); 
		} 
	} 
}

Output:

Output


The total number of key/value pairs in myD are : 6
Key = Belgium
Key = China
Key = France
Key = Germany
Key = Oman
Key = Spain

Example 2:

Let's consider another example to incorporate the dictionary feature in C#.

Example


using System; 
using System.Collections.Generic; 

class Dic{ 


	public static void Main() 
	{ 

		// Create a new dictionary which consists of string keys
		SortedDictionary<int, int> myD = 
		new SortedDictionary<int, int>(); 

		//The key and value pairs are added to the dictionary
		myD.Add(1,5); 
		myD.Add(2,6); 
		myD.Add(3,7); 
		myD.Add(4,8); 
		myD.Add(5,9); 
		myD.Add(0,54); 

		// to find the count of the keys
		Console.WriteLine("The total number of key/value pairs"
			+ " in myD are : " + myD.Count); 

		//For getting only the keys, make use of the Keys property. 
		SortedDictionary<int, int>.KeyCollection keyColls = 
													myD.Keys; 

		//The KeyCollection components are strongly typed using the type // that was defined for dictionary // keys. 
		foreach(int i in keyColls) 
		{ 
			Console.WriteLine("Key = {0}", i); 
		} 
	} 
}

Output:

Output


The total number of key/value pairs in myD are : 6
Key = 0
Key = 1
Key = 2
Key = 3
Key = 4
Key = 5

Syntax:

Return Value:

Key characteristics include:

Complexity and performance:

Considerations as well as Use Cases:

Best Practices and Considerations:

Example 1:

Example 2:

Input Required