SortedDictionary<T> in C#

DevSniper
Published : 03 March 2024

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C#Dictionary Language-Concepts C# Collection

Namespace :- System.Collections.Generic

Assembly :- System.Collections.dll

Signature :-

public class SortedDictionary<TKey,TValue> :

System.Collections.Generic.ICollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>,
System.Collections.Generic.IDictionary<TKey,TValue>,
System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,TValue>>,
System.Collections.Generic.IReadOnlyCollection<System.Collections.Generic.KeyValuePair<TKey,TValue>>,
System.Collections.Generic.IReadOnlyDictionary<TKey,TValue>,
System.Collections.IDictionary

It is used to store key/value pairs in the sorted order of key
it does not store duplicate key. key must be unique.
Key can not be null
Value can be null in the case of reference type
It allowed only the same type of key/value pair data
Generic implementation of SortedDictionary<TKey,TValue> class is a binary search tree (BST). With retrieval complexity O(log n)
SortedDictionary<TKey,TValue> requires higher memory than SortedList<TKey,TValue>.
For unsorted data , SortedDictionary<TKey,TValue> performs faster insertion and removal operations in O(log n) compared to SortedList<TKey,TValue> which performs these operations in O(n)
SortedList<TKey,TValue> is faster than SortedDictionary<TKey,TValue> if list is created all at once from sorted data.

SortedDictionary<TKey,TValue> Constructors

public SortedDictionary ();
public SortedDictionary (System.Collections.Generic.IComparer<TKey>? comparer);
public SortedDictionary (System.Collections.Generic.IDictionary<TKey,TValue> dictionary);
public SortedDictionary (System.Collections.Generic.IDictionary<TKey,TValue> dictionary, System.Collections.Generic.IComparer<TKey>? comparer);

SortedDictionary<TKey,TValue> Properties

Comparer :- public System.Collections.Generic.IComparer<TKey> Comparer { get; }
Gets the IComparer<T> that is used to sort/order element of the SortedDictionary<TKey,TValue>.
Count :- public int Count { get; }
Gets the number of key/value pairs that is present in the SortedDictionary<TKey,TValue>. it is an O(1) operation.
Item[TKey] :- public TValue this[TKey key] { get; set; }
Gets or sets the value linked with the specified key. Getting and setting the value of this property, both is an O(log n) operation.
Keys :- public System.Collections.Generic.SortedDictionary<TKey,TValue>.KeyCollection Keys { get; }
Gets a KeyCollection containing the keys in the SortedDictionary<TKey,TValue>. it is also an O(1) operation.
Values :- public System.Collections.Generic.SortedDictionary<TKey,TValue>.ValueCollection Values { get; }
Gets a ValueCollection containing the values in the SortedDictionary<TKey,TValue>. it is an O(1) operation.

Creating and adding element in SortedDictionary<TKey,TValue>

1. initialize the SortedDictionary<TKey,TValue> with initial values

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        var dict = new SortedDictionary<string,string> {
            {"language","C#"},
            {"topic","SortedDictionary"},
            {"label","Beginner"}
        };
        Console.WriteLine("We are learning "+dict["language"]+" "+dict["topic"] +" and level : "+dict["label"]);
         Console.WriteLine("------------------loop------------");
        foreach (KeyValuePair<string, string> kv in dict) {
            Console.WriteLine("K: "+ kv.Key+" V: "+kv.Value);
        }
    }
}

We are learning C# SortedDictionary and level : Beginner
------------------loop------------
K: label V: Beginner
K: language V: C#
K: topic V: SortedDictionary

2. Direct Assign to add new element in SortedDictionary<TKey,TValue>

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        var dict = new SortedDictionary<string,string>();
        dict["language"]="C#";
        dict["topic"]="SortedDictionary";
        dict["label"]="Beginner";
        Console.WriteLine("We are learning "+dict["language"]+" "+dict["topic"] +" and level : "+dict["label"]);
        Console.WriteLine("------------------loop------------");
        foreach (KeyValuePair<string, string> kv in dict) {
            Console.WriteLine("K: "+ kv.Key+" V: "+kv.Value);
        }
    }
}

We are learning C# SortedDictionary and level : Beginner
------------------loop------------
K: label V: Beginner
K: language V: C#
K: topic V: SortedDictionary

3. Using Add() Method to add new element in SortedDictionary<TKey,TValue>

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        var dict = new SortedDictionary<string,string>();
        dict.Add("language","C#");
        dict.Add("topic","SortedDictionary");
        dict.Add("label","Beginner");
        Console.WriteLine("We are learning "+dict["language"]+" "+dict["topic"] +" and level : "+dict["label"]);
        Console.WriteLine("------------------loop------------");
        foreach (KeyValuePair<string, string> kv in dict) {
            Console.WriteLine("K: "+ kv.Key+" V: "+kv.Value);
        }
    }
}

We are learning C# SortedDictionary and level : Beginner
------------------loop------------
K: label V: Beginner
K: language V: C#
K: topic V: SortedDictionary

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