loose coupling of classes over interface

Ganesh Jangam

If i make change in IDatabase interface then it will affect, and at run while creating object of CustomerRepository we still worry about what i have to pass for constructor parameter, Does that mean still there is tight coupling for classes over interface ?

class CustomerRepository
{
private readonly IDatabase database;
public CustomerRepository(IDatabase database)
{
this.database = database;
}
public void Add(string CustomerName)
{
database.AddRow("Customer", CustomerName);
}
}
interface IDatabase
{
void AddRow(string Table, string Value);
}
class Database : IDatabase
{
public void AddRow(string Table, string Value)
{
}
}

2 Replies

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Nitin Sontakke8y ago
Accepted answer
Well, it depends and the answer is yes and no, depending on the perspective and how far can you strech the concept of loose coupling. Ultimately, we got to stop somewhere. The point is 'did you try to achieve maximum level of loose coupling or not'.

For example, in above case, it is not quite clear what kind of changes are you intending to do in IDatabase interface. For example, you are of course free to add another method if you wish.

If you are referring to adding another parameter to AddRow, then yes interface will be broken. However, there is a way around that too.

You can have yet another class called AddRowParameter and have that as a parameter to the AddRow method as demonstrated below:
public class AddRowParameter
{
  public String Table {get; set;}
  public String Value {get; set;}
}

interface IDatabase
{
  void AddRow(AddRowParameter addRowParameter)
}
In this case you are free to add more properties to the class AddRowParameter and interface is not broken either.
Hope you get the point.
Nitin Sontakke8y ago
https://www.c-sharpcorner.com/forums/how-to-display-department-name-along-with-number-of-employe