C# default constructor access modifier

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One of our YouTube channel subscribers faced this c# question in an interview for an entry level c# developer role. So here is the question.


What is the Access Modifier of the default parameter-less constructor in C#
The answer is Public


Let's prove this. Consider the following Customer class

class Customer
{
}

The Customer class does not have an explicit constructor defined. In C#, if we do not provide an explicit constructor, a default parameter-less constructor is automatically provided. The access modifier for that constructor is Public.

We can prove this using the following reflection code.

using System;
using System.Reflection;

namespace Demo
{
    class Program
    {
        static void Main(string[] args)
        {
            Type type = typeof(Customer);
            // Type.EmptyTypes represents an Empty Type[] array
            // We use an Empty Type[] array to get the Constructor that 
            // takes no parameters
            ConstructorInfo constructorInfo = type.GetConstructor(Type.EmptyTypes);
            Console.WriteLine("Is Constructor : " + constructorInfo.IsConstructor);
            Console.WriteLine("Is Public : " + constructorInfo.IsPublic);
        }
    }

    class Customer
    {
    }
}

Output:
Is Constructor : True
Is Public : True

The following code checks if the constructor is private or protected

using System;
using System.Reflection;

namespace Demo
{
    class Program
    {
        static void Main(string[] args)
        {
            Type type = typeof(Customer);
            ConstructorInfo constructorInfo = type.GetConstructor(
                BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic,
                null, Type.EmptyTypes, null);
            Console.WriteLine("Is Constructor : " + constructorInfo.IsConstructor);
            Console.WriteLine("Is Protected : " + constructorInfo.IsFamily);
        }
    }

    class Customer
    {
        protected Customer()
        { }
    }
}