How do programmers practice code reuse

Question

I\'ve been a bad programmer because I am doing a copy and paste. An example is that everytime i connect to a database and retrieve a recordset, I will copy the previous code and

Answer 1

Depending on the size of the project can change the answer.

For a smaller project I would recommend setting up a DatabaseHelper class that does all your DB access. It would just be a wrapper around opening/closing connections and execution of the DB code. Then at a higher level you can just write the DBCommands that will be executed.

A similar technique could be used for a larger project, but would need some additional work, interfaces need to be added, DI, as well as abstracting out what you need to know about the database.

You might also try looking into ORM, DAAB, or over to the Patterns and Practices Group

As far as how to prevent the ole C&P? - Well as you write your code, you need to periodically review it, if you have similar blocks of code, that only vary by a parameter or two, that is always a good candidate for refactoring into its own method.

Now for my pseudo code example:

Function GetCustomer(ID) as Customer
   Dim CMD as New DBCmd("SQL or Stored Proc")
   CMD.Paramaters.Add("CustID",DBType,Length).Value = ID
   Dim DHelper as New DatabaseHelper
   DR = DHelper.GetReader(CMD)
   Dim RtnCust as New Customer(Dx)
   Return RtnCust
End Function

Class DataHelper
  Public Function GetDataTable(cmd) as DataTable
    Write the DB access code stuff here.
    GetConnectionString
    OpenConnection
    Do DB Operation
    Close Connection
  End Function
  Public Function GetDataReader(cmd) as DataReader
  Public Function GetDataSet(cmd) as DataSet
  ... And So on ...
End Class