Getting Selected Index With DataGridView Using MVP and Winforms

Question

I am creating a database-driven application using winforms and the MVP(Model View Presenter) pattern and I'm running into an issue that I cannot seem to solve. I have wriiten a data access layer which pulls all my customer information from a table and stores it into a List. Now since I'm using the MVP pattern my datagrid view is an object, I have bound my List in my data access layer so it displays in the datagris view when I press the "View" button but what I'm having difficulty with is getting the selected index and displaying that row of information inside textboxes on another form. If I wasn't using the MVP pattern I could use the selectedIndex property but since my view properities are using interfaces I am not sure how I would go about getting the slected index. Here is my MVP layout:

View:

01

public interface IHomeView
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       {
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           string SearchText { get; set; }
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           string ConnectionStatus { get; set; }
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           object ViewTables { get; set; }
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           object DataGridCustomers { get; set; }
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           object DataGridCustomersSelectedRow { get; set; }
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           event EventHandler<EventArgs> PopulateData;
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           event EventHandler<EventArgs> SearchData;
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           event EventHandler<EventArgs> PopulateSearchData;
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           event EventHandler<EventArgs> Connectionstatus;
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           event EventHandler<EventArgs> DisplayForm;
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       }

Presenter: 01

public class HomePresenter
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       {
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           private readonly IHomeView view;
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           private SearchRepository repository;
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           private CustomerRepository customerRepository;
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           private List<CustomerModel> customerModel;
08

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           public HomePresenter(IHomeView view)
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           {
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               this.view = view;
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               InitialiseEvents();
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               repository = new SearchRepository();
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               customerRepository = new CustomerRepository();
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               customerModel = customerRepository.GetAllCustomers();
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           }
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           private void InitialiseEvents()
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           {
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               view.PopulateData += PopulateData;
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               view.SearchData += SearchData;
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               view.PopulateSearchData += PopulateSearchCriteria;
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               view.Connectionstatus += ConnectionStatus;
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               view.DisplayForm += DisplayForm;
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           }
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           private void PopulateData(object sender, EventArgs e)
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           {
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               try
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               {
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                   try
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                   {
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                       //view.DataGridCustomers = customerRepository.GetAllCustomers().Where(value => cm.LastName.Equals(view.SearchText)).ToList();
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                       view.DataGridCustomers = customerRepository.GetAllCustomers();
35

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                   }
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                   catch (Exception ex)
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                   {
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                   }
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               }
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               catch (Exception ex)
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               {
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               }
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               finally
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               {
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                   //MessageBox.Show(customerRepository.Message);
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               }
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           }
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           private void SearchData(object sender, EventArgs e)
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           {
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               if (view.ViewTables != null)
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               {
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                 view.DataGridCustomers = customerRepository.GetAllCustomers().Where(cm => cm.LastName.Equals(view.SearchText)).ToList();
58

59

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               }
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               else
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               {
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                  MessageBox.Show("Please select a table");
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               }
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           }
66

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           private void PopulateSearchCriteria(object sender, EventArgs e)
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           {
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               if (view.ViewTables != null)
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               {
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               }
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           }
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           private void ConnectionStatus(object sender, EventArgs e)
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           {
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               if (repository != null)
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               {
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                   view.ConnectionStatus = "Online";
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               }
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               else
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               {
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                   view.ConnectionStatus = "Offline";
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               }
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           }
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           private void DisplayForm(object sender, EventArgs e)
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           {
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               frmCustomer customerView = new frmCustomer();
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               customerView.ShowDialog();
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           }
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       }

Model: 01

    public class CustomerModel
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        {
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            public string ID { get; set; }
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            public string Title { get; set; }
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            public string FirstName { get; set; }
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            public string LastName { get; set; }
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            public string DateOfBith { get; set; }
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            public string Natins { get; set; }
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            public string Email { get; set; }
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            public string Allowance { get; set; }
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        }

Data Access Layer Method:

01

    public List<CustomerModel> GetAllCustomers()
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           {
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               List<CustomerModel> customerList = new List<CustomerModel>();
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               try
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               {
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                   _command.CommandText = "SELECT * FROM customer";
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                   _command.CommandType = CommandType.Text;
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                   _connection.Open();
10

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                   OleDbDataReader reader = _command.ExecuteReader();
12

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                   while (reader.Read())
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                   {
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                       CustomerModel customerModel = new CustomerModel();
16

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                       customerModel.ID = Convert.ToInt32(reader["custid"]).ToString();
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                       customerModel.Title = reader["title"].ToString();
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                       customerModel.FirstName = reader["firstname"].ToString();
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                       customerModel.LastName = reader["lastname"].ToString();
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                       customerModel.DateOfBith = reader["dob"].ToString();
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                       customerModel.Natins = reader["natins"].ToString();
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                       customerModel.Email = reader["email"].ToString();
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                       customerModel.Allowance = Convert.ToDouble(reader["allowance"]).ToString();
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                       customerList.Add(customerModel);
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                   }
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               }
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               catch (Exception ex)
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               {
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                   Message = ex.Message;
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               }
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               finally
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               {
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                   CloseDatabase();
36

37
               }
38

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               return customerList;
40
           }

I realise that some part of the code could be cleaned up but I wanted to give you a general idea of how I'm laying out my architecture. As for solutions I have tried to loop through the datagrid and get the index basied on that and creating a get method to return the current row (which works but I can't set values to it with it being read only) but I can't see a clean way which doesn't break the MVP pattern.

I should clarify that I'm not looking for complete code solutions but rather to be pointed in the right direction.

Thank you

Answer 1

SelectedIndex returns an int .

Let's call this int currentSelectionIndex .

When the View button is clicked, the event fires a method that gets currentSelectionIndex and sends it to your Data Access Layer that contains the customerList .

Returning customerList[currentSelectionIndex] will return the currently selected CustomerModel, provided that customerList is in the same sorting order as the datagrid.