Authenticating to Azure SQL database without using UserID and Password

Question

I am trying to authenticate to my Azure SQL through c# using this code. The code works but I do not want to use my UserID and Password. Can I use anything else to authenticate? Token?

using System;
using System.Data.SqlClient;
using System.Text;

namespace sqltest
{
    class Program
    {
        static void Main(string[] args)
        {
            try 
            { 
                SqlConnectionStringBuilder builder = new SqlConnectionStringBuilder();
                builder.DataSource = "<server>.database.windows.net"; 
                builder.UserID = "<username>";            
                builder.Password = "<password>";     
                builder.InitialCatalog = "<database>";

                using (SqlConnection connection = new SqlConnection(builder.ConnectionString))
                {
                    Console.WriteLine("\nQuery data example:");
                    Console.WriteLine("=========================================\n");

                    StringBuilder sb = new StringBuilder();
                    sb.Append("SELECT TOP 20 pc.Name as CategoryName, p.name as ProductName ");
                    sb.Append("FROM [SalesLT].[ProductCategory] pc ");
                    sb.Append("JOIN [SalesLT].[Product] p ");
                    sb.Append("ON pc.productcategoryid = p.productcategoryid;");
                    String sql = sb.ToString();

                    using (SqlCommand command = new SqlCommand(sql, connection))
                    {
                        connection.Open();
                        using (SqlDataReader reader = command.ExecuteReader())
                        {
                            while (reader.Read())
                            {
                                Console.WriteLine("{0} {1}", reader.GetString(0), reader.GetString(1));
                            }
                        }
                    }                    
                }
            }
            catch (SqlException e)
            {
                Console.WriteLine(e.ToString());
            }
            Console.ReadLine();
        }
    }
}

Answer 1

You can use 2 things.
1. Use Managed Identities for Azure Resources
This is the recommended approach, in this method, code will generate a token using azure identities.

.NET Framework 4.6 or higher or .NET Core 2.2 or higher is required to use the access token method.

For More Information -> https://learn.microsoft.com/en-us/azure/active-directory/managed-identities-azure-resources/tutorial-windows-vm-access-sql

2. Store sensitive information (username/password/connection string) in azure key vault
https://learn.microsoft.com/en-us/azure/key-vault/tutorial-net-create-vault-azure-web-app