Introduction
A dictionary type represents a collection of keys and values pair of data. The Dictionary class is defined in the System.Collections.Generic namespace is a generic class that can store data types as keys and values. Each key must be unique in the collection. Before you use the Dictionary class in your code, you must import the System.Collections.Generic namespace using the following line.
using System.Collections.Generic;
Creating a Dictionary
The Dictionary class constructor takes key and value data types. Both types are generic, so that they can be any .NET data type.
The following The Dictionary class is a generic class that can store data types. This class, defined in the code snippet, creates a dictionary where both keys and values are string types.
Dictionary<string, string> EmployeeList = new Dictionary<string, string>();
The following code snippet adds items to the dictionary.
EmployeeList.Add("Mahesh Chand", "Programmer");
EmployeeList.Add("Praveen Kumar", "Project Manager");
EmployeeList.Add("Raj Kumar", "Architect");
EmployeeList.Add("Nipun Tomar", "Asst. Project Manager");
EmployeeList.Add("Dinesh Beniwal", "Manager");
The following code snippet creates a dictionary where the key type is a string, and the value type is a short integer.
Dictionary<string, Int16> AuthorList = new Dictionary<string, Int16>();
The following code snippet adds items to the dictionary.
AuthorList.Add("Mahesh Chand", 35);
AuthorList.Add("Mike Gold", 25);
AuthorList.Add("Praveen Kumar", 29);
AuthorList.Add("Raj Beniwal", 21);
AuthorList.Add("Dinesh Beniwal", 84);
We can also limit the size of a dictionary. The following code snippet creates a dictionary where the key type is a string, the value type is float, and the total number of items it can hold is 3.
Dictionary<string, float> PriceList = new Dictionary<string, float>(3);
The following code snippet adds items to the dictionary.
PriceList.Add("Tea", 3.25f);
PriceList.Add("Juice", 2.76f);
PriceList.Add("Milk", 1.15f);
Read more >> Using C# Dictionary Class