具有C＃接口的继承窗口表单

Question

I have a base windows forms class which contains two buttons: Ok and Cancel. This base form implements the interface IBaseForm :

public interface IBaseForm
{
  string FormText {get;set;}
  DialogResult ShowView(IWin32Window owner);
}

public partial class BaseForm : IBaseForm
{
  ...
}

Next I have a window class which inherits from BaseForm and implements another interface IItem :

public interface IItem : IBaseForm // here is problem
{
  string ItemName {get; set;}
  ...
}

public partial class AddItemForm : BaseForm, IItem
{
  ...
  // I don't have to implement IItem here, because it is implement in BaseForm
}

The problem is with the inheritance of IBaseForm ; I have to inherit it two times. In code I have:

IItem view = new AddItemForm();
view.FormText = "Add new item";

If I remove inheritance from IItem , view.FormText will be not visible. If I remove the inheritance from BaseForm I have to implement IBaseForm in each AddItemForm . I've only showed one itemForm but it is a lot, and I have to implement this many times.

How I can resolve this problem?

Answer 1

There isn't another way to do this. BaseForm is a class, whereas IItem is an unrelated interface. Neither is a 'super' or 'base' of the other, so you need to inherit from IBaseForm in both of them.

Answer 2

I don't really understand the problem; the code you've written compiles and runs just fine as you've written it.

AddItemForm inherits BaseForm 's implementation of IBaseForm , so doesn't have to re-implement IBaseForm .