C# Online Compiler | .NET Fiddle

using System;
					
public class Program
{
	
	public class Product
	{
		public string ProductCode { get;set;}
		public string ProductName { get;set;}
		public string ProductDescription { get;set;}
		public int ProductPrice { get;set;}
		
		public Product(string Code, string Name, string Description, int Price)
		{
			if(String.IsNullOrWhiteSpace(Code))
				throw new ArgumentNullException("Product Code cannot be empty");
			else
				this.ProductCode =Code;
			
			if(String.IsNullOrWhiteSpace(Name))
				throw new ArgumentNullException("Product Name cannot be empty");
			else
				this.ProductName= Name;
			
			if(String.IsNullOrWhiteSpace(Description))
				throw new ArgumentNullException("Product Description cannot be empty");
			else
				this.ProductDescription = Description;
			
			if(Price <=0 )
				throw new ArgumentNullException("Product Price should be greater than 0");
			else
				this.ProductPrice= Price;
				
		}
		
		public void DisplayValues()
		{
			Console.WriteLine("Product Code - {0}", this.ProductCode);
			Console.WriteLine("Product Name - {0}", this.ProductName);	
			Console.WriteLine("Product Description - {0}", this.ProductDescription);
			Console.WriteLine("Product Price - {0}", this.ProductPrice);
		}
	}
	
	public static void Main()
	{
		try
		{
			Console.WriteLine("With null value");
			Product prod1 = new Product(null, null,null,2);
			prod1.DisplayValues();
		}
		catch(Exception e)
		{
			Console.WriteLine(e.Message);
		}
							  
		Console.WriteLine("\nWithout null values");
		
		Product prod2 = new Product("640", "Nokia 640 XL","Nokia 640 XL LTE",15000);
		prod2.DisplayValues();
		
		
		
	}
}

 
using System;
                    
public class Program
{
    
    public class Product
    {
        public string ProductCode { get;set;}
        public string ProductName { get;set;}
        public string ProductDescription { get;set;}
        public int ProductPrice { get;set;}
        
        public Product(string Code, string Name, string Description, int Price)
        {
            if(String.IsNullOrWhiteSpace(Code))
                throw new ArgumentNullException("Product Code cannot be empty");
            else
                this.ProductCode =Code;
            
            if(String.IsNullOrWhiteSpace(Name))
                throw new ArgumentNullException("Product Name cannot be empty");
            else
                this.ProductName= Name;
            