Question

I’m having problems with the code below. Whenever I create a new instance of the class below and call “Select” I get an object reference not set to an instance of an object on the “this.db”

namespace SPI {

    class CompaniesDB
    {
        private DataContainer db;

        public void New() {
            this.db = new DataContainer();
        }
        public Company Select(int companyID) {
            return this.db.Company_Get(companyID).SingleOrDefault();
        }
    }
}

Can someone point me at why my “New()” doesn’t seem to be creating a new object?

I’m relatively new to C#.

Answer 1

You don’t name a constructor as New. You name it with the class Name.

Try

namespace SPI { 

    class CompaniesDB 
    { 
        private DataContainer db; 

        public CompaniesDB() { 
            this.db = new DataContainer(); 
        } 
        public Company Select(int companyID) { 
            return this.db.Company_Get(companyID).SingleOrDefault(); 
        } 
    } 
} 

MSDN page on constructors: http://msdn.microsoft.com/en-us/library/ms173115.aspx