SortedList Collection in C#

The SortedList collection represents Key-Value pairs in the ascending order of the keys by default. The elements can be accessed by both the key and index as required.

Constructors in SortedList Collection

The different constructors and their description is given as follows:

Table: Constructors in SortedList in C#

Source: MSDN

Properties in SortedList Collection

The different properties and their description is given as follows:

Table: Properties in SortedList in C#

Source: MSDN

Methods in SortedList Collection

The different methods and their description is given as follows:

Table: Methods in SortedList in C#

SortedList Operations

Some of the SortedList operations are given as follows:

Adding elements in SortedList

Elements can be added to the SortedList using the Add() method. It adds the specified key and value pairs to the dictionary. The program that demonstrates this is given as follows:

Source Code: Program to add elements in SortedList in C#

using System;
using System.Collections.Generic;
namespace SortedListDemo
{
  class Example
  {
     static void Main(string[] args)
     {
       SortedList<int, string> s = new SortedList<int, string>();
       s.Add(9,"Harry");
       s.Add(2,"Sally");
       s.Add(3,"Clarke");
       s.Add(1,"James");
       s.Add(7,"Emma");
       s.Add(6,"Susan");
       Console.WriteLine("SortedList elements are as follows:");
       foreach (KeyValuePair<int, string> i in s)
       {
           Console.WriteLine("Key: {0}     Value: {1}", i.Key, i.Value);
       }
     }
  }
}

The output of the above program is as follows:

SortedList elements are as follows:
Key: 1     Value: James
Key: 2     Value: Sally
Key: 3     Value: Clarke
Key: 6     Value: Susan
Key: 7     Value: Emma
Key: 9     Value: Harry

Deleting elements from SortedList

An element can be deleted from the SortedList using the Remove() method. This method deletes the key, value pair with the specific key that is provided. The program that demonstrates this is given as follows:

Source Code: Program to delete elements from SortedList in C#

using System;
using System.Collections.Generic;
namespace SortedListDemo
{
  class Example
  {
     static void Main(string[] args)
     {
       SortedList<int, string> s = new SortedList<int, string>();
       s.Add(9,"Harry");
       s.Add(2,"Sally");
       s.Add(3,"Clarke");
       s.Add(1,"James");
       s.Add(7,"Emma");
       s.Add(6,"Susan");  
       Console.WriteLine("Original SortedList elements:");
       foreach (KeyValuePair<int, string> i in s)
       {
           Console.WriteLine("Key: {0}     Value: {1}", i.Key, i.Value);
       }
       s.Remove(3);
       s.Remove(6);
       Console.WriteLine("SortedList elements after deletion:");
       foreach (KeyValuePair<int, string> i in s)
       {
           Console.WriteLine("Key: {0}     Value: {1}", i.Key, i.Value);
       }
     }
  }
}

The output of the above program is as follows:

Original SortedList elements:
Key: 1     Value: James
Key: 2     Value: Sally
Key: 3     Value: Clarke
Key: 6     Value: Susan
Key: 7     Value: Emma
Key: 9     Value: Harry

SortedList elements after deletion:
Key: 1     Value: James
Key: 2     Value: Sally
Key: 7     Value: Emma
Key: 9     Value: Harry

Finding an element in SortedList

The ContainsKey() method finds if a key is present in the SortedList or not. If it is present, ContainsKey() returns TRUE and otherwise it returns FALSE. Similarly, ContainsValue() finds if a value is present in the Dictionary or not. If it is present, ContainsValue() returns TRUE and otherwise it returns FALSE.

The program that demonstrates this is given as follows:

Source Code: Program to find an element in SortedList in C#

using System;
using System.Collections.Generic;
namespace SortedListDemo
{
  class Example
  {
     static void Main(string[] args)
     {
       SortedList<int, string> s = new SortedList<int, string>();
       s.Add(9,"Harry");
       s.Add(2,"Sally");
       s.Add(3,"Clarke");
       s.Add(1,"James");
       s.Add(7,"Emma");
       s.Add(6,"Susan");
       Console.WriteLine("SortedList elements:");
       foreach (KeyValuePair<int, string> i in s)
       {
           Console.WriteLine("Key: {0}     Value: {1}", i.Key, i.Value);
       }
       Console.WriteLine();
       Console.WriteLine("The key 9 is present in SortedList: " + s.ContainsKey(3));
       Console.WriteLine("The value Monica is present in SortedList: " + s.ContainsValue("Monica"));
     }
  }
}

The output of the above program is as follows:

SortedList elements:
Key: 1     Value: James
Key: 2     Value: Sally
Key: 3     Value: Clarke
Key: 6     Value: Susan
Key: 7     Value: Emma
Key: 9     Value: Harry

The key 9 is present in SortedList: True
The value Monica is present in SortedList: False

Check whether the SortedList has a fixed size or not

Use the IsFixedSize() property in C# to get a value stating whether the SortedList has a fixed size or not

Let us see an example:

Source Code: Program that checks whether the SortedList has a fixed size or not in C#

using System;
using System.Collections;
namespace SortedListExample {
  class Example {
     static void Main(string[] args) {
        SortedList sList = new SortedList();
        sList.Add("L001", "Elyse");
        sList.Add("L002", "Meg");
        sList.Add("L003", "Sarah");
        sList.Add("L004", "Nicole");
        sList.Add("L005", "Alyssa");
        sList.Add("L006", "Megan");
        sList.Add("L007", "Jess");
        sList.Add("L008", "Belinda");
        Console.WriteLine("Fixed Size? " + sList.IsFixedSize);
     }
  }
}

The above program gives the following output:

Fixed Size? False

Check whether the SortedList is read only or not

Use the IsFixedSize() property in C# to get a value stating whether the SortedList is read only or not

Let us see an example:

Source Code: Program that checks whether the SortedList is read only or not in C#

using System;
using System.Collections;
namespace SortedListExample {
  class Example {
     static void Main(string[] args) {
        SortedList sList = new SortedList();
        sList.Add("L001", "Elyse");
        sList.Add("L002", "Meg");
        sList.Add("L003", "Sarah");
        sList.Add("L004", "Nicole");
        sList.Add("L005", "Alyssa");
        sList.Add("L006", "Megan");
        sList.Add("L007", "Jess");
        sList.Add("L008", "Belinda");
        Console.WriteLine("Read Only? " + sList.IsReadOnly);
     }
  }
}

The above program gives the following output:

Read Only? False

Get the keys in the SortedList

Use the Keys property to get the keys in the SortedList. Let us see how to implement it in C#:

Source Code: Program that gets the keys in the SortedList in C#

using System;
using System.Collections;
namespace Demo {
  class Example {
     static void Main(string[] args) {
        SortedList sList = new SortedList();
        sList.Add("A", "Mic");
        sList.Add("B", "Speaker");
        sList.Add("C", "Devices");
        sList.Add("D", "Screenguards");
        sList.Add("E", "Memory Cards");
        ICollection res = sList.Keys;
        foreach (string k in res) {
           Console.WriteLine(k);
        }
     }
  }
}

The above program gives the following output:

A
B
C
D
E

Get the maximum size of the SortedList

Use the Capacity property to get the maximum size of the SortedList:

Source Code: Program that get the maximum size of the SortedList in C#

using System;
using System.Collections;
namespace SortedListExample {
  class Example {
     static void Main(string[] args) {
        SortedList sList = new SortedList();
        sList.Add("AB01", "Dirk");
        sList.Add("AB02", "Nolan");
        sList.Add("AB03", "Carst");
        sList.Add("AB04", "Darren");
        sList.Add("AB05", "Daan");
        sList.Add("AB06", "Andre");
        sList.Add("AB07", "Timm");
        sList.Add("AB08", "Logan");
        Console.WriteLine("Capacity = " + sList.Capacity);
     }
  }
}

The above example gives the following output:

Capacity = 16

Count the number of elements in a SortedList

Use the Count property to count the number of elements in a SortedList. Let us see an example:

Source Code: Program that counts the number of elements in a SortedList in C#

using System;
using System.Collections;
namespace SortedListExample {
  class Example {
     static void Main(string[] args) {
        SortedList sList = new SortedList();
        sList.Add("AB01", "Dirk");
        sList.Add("AB02", "Nolan");
        sList.Add("AB03", "Carst");
        sList.Add("AB04", "Darren");
        sList.Add("AB05", "Daan");
        sList.Add("AB06", "Andre");
        sList.Add("AB07", "Timm");
        sList.Add("AB08", "Logan");
        Console.WriteLine("Capacity = " + sList.Capacity);
        Console.WriteLine("Count = " + sList.Count);
     }
  }
}

The above program displays the following output:

Capacity = 16
Count = 8

Values property of SortedList Collection

The Values property allows a user to display the values of a SortedList. Let us see an example to display only the values:

Source Code: Program that demonstrates the values property in a SortedList in C#

using System;
using System.Collections;
namespace SortedListExample {
  class Example {
     static void Main(string[] args) {
        SortedList sList = new SortedList();
        sList.Add("AB01", "Dirk");
        sList.Add("AB02", "Nolan");
        sList.Add("AB03", "Carst");
        sList.Add("AB04", "Darren");
        sList.Add("AB05", "Daan");
        sList.Add("AB06", "Andre");
        sList.Add("AB07", "Timm");
        sList.Add("AB08", "Logan");
        Console.WriteLine("Count = " + sList.Count);
        Console.WriteLine("Here are the values:");
        foreach (string res in sList.Values)
       {
           Console.WriteLine(res);
       }
     }
  }
}

The above program displays the following output:

Count = 8
Here are the values:
Dirk
Nolan
Carst
Darren
Daan
Andre
Timm
Logan