How to: Initialize Objects by Using an Object Initializer (C# Programming Guide)

public class Program
{
    public static void Main()
    {

        // Declare a StudentName by using the constructor that has two parameters.
        StudentName student1 = new StudentName("Craig", "Playstead");

        // Make the same declaration by using a collection initializer and sending 
        // arguments for the first and last names. The default constructor is 
        // invoked in processing this declaration, not the constructor that has
        // two parameters.
        StudentName student2 = new StudentName
        {
            FirstName = "Craig",
            LastName = "Playstead",
        };

        // Declare a StudentName by using a collection initializer and sending 
        // an argument for only the ID property. No corresponding constructor is
        // necessary. Only the default constructor is used to process object 
        // initializers.
        StudentName student3 = new StudentName
        {
            ID = 183
        };

        // Declare a StudentName by using a collection initializer and sending
        // arguments for all three properties. No corresponding constructor is 
        // defined in the class.
        StudentName student4 = new StudentName
        {
            FirstName = "Craig",
            LastName = "Playstead",
            ID = 116
        };

        System.Console.WriteLine(student1.ToString());
        System.Console.WriteLine(student2.ToString());
        System.Console.WriteLine(student3.ToString());
        System.Console.WriteLine(student4.ToString());
    }

    // Output:
    // Craig  0
    // Craig  0
    //   183
    // Craig  116
}

public class StudentName
{
    // The default constructor has no parameters. The default constructor 
    // is invoked in the processing of object initializers. 
    // You can test this by changing the access modifier from public to 
    // private. The declarations in Main that use object initializers will 
    // fail.
    public StudentName() { }

    // The following constructor has parameters for two of the three 
    // properties. 
    public StudentName(string first, string last)
    {
        FirstName = first;
        LastName = last;
    }

    // Properties.
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public int ID { get; set; }

    public override string ToString()
    {
        return FirstName + "  " + ID;
    }
}

List<StudentName> students = new List<StudentName>()
{
  new StudentName {FirstName="Craig", LastName="Playstead", ID=116},
  new StudentName {FirstName="Shu", LastName="Ito", ID=112},
  new StudentName {FirstName="Gretchen", LastName="Rivas", ID=113},
  new StudentName {FirstName="Rajesh", LastName="Rotti", ID=114}
};