Note: This article was originally published in 2011. Some steps, commands, or software versions may have changed. Check the current .Net documentation for the latest information.

In this step-by-step guide, you’ll learn initialize a .net dictionary at the variable declaration level. .

Prerequisites

Before you begin, make sure you have:

  • Visual Studio or .NET CLI installed
  • .NET Framework or .NET Core SDK
  • Basic C# programming knowledge

How to: Initialize a Dictionary with a Collection Initializer

Sometimes in your project you want to initialize a Dictionary or other sort of collection at the declaration level so you don’t have to manually use the .add() methods and write a separate method in which to execute them. A prime example is a dictionary that is going to be static and used across the entire application and you don’t expect it to change. The code below offers an example of how to initialize a dictionary when you’re declaring the variable:

Dictionary<int, StudentInfo> students = new Dictionary<int, StudentInfo>()
{
    { 111, new StudentInfo {FirstName="Sachin", LastName="Karnik", PhoneNumber="123-456-7890"}},
    { 112, new StudentInfo {FirstName="Dina", LastName="Salimzianova", PhoneNumber="123-456-7890"}},
    { 113, new StudentInfo {FirstName="Andy", LastName="Ruth", PhoneNumber="123-456-7890"}}
};


StudentInfo

Summary

You’ve successfully learned initialize a .net dictionary at the variable declaration level. If you run into any issues, double-check the prerequisites and ensure your .Net environment is properly configured.