DataGridViewComboBoxCell Value Not Updating When Set Programmatically C# Winforms

Question

I've read all the similiar posts about this darn control (DataGridViewComboBoxCell) and setting it's value programmatically but implementing all the suggestions hasn't worked. I could probably change the UI to get around this problem but I don't like to be beat!

  private void PopulateAreaForRoleAssociation()
    {

        // If businessRoleList is null then no data has been bound to the dgv so return
        if (businessRoleList == null)
            return;

        // Ensure businessArea repository is instantiated
        if (businessAreaRepository == null)
            businessAreaRepository = new BusinessAreaRespository();

        // Get a reference to the combobox column of the dgv
        DataGridViewComboBoxColumn comboBoxBusinessAreaColumn = (DataGridViewComboBoxColumn)dgvBusinessRole.Columns["BusinessArea"];

        // Set Datasource properties to fill combobox
        comboBoxBusinessAreaColumn.DisplayMember = "Name";
        comboBoxBusinessAreaColumn.ValueMember = "Id";
        comboBoxBusinessAreaColumn.ValueType = typeof(Guid);

        // Fill combobox with businessarea objects from list out of repository
        comboBoxBusinessAreaColumn.DataSource = businessAreaRepository.GetAll();

        // loop through the businessRoles list which the dgv is bound to and get out each dgv row based upon the current id in the loop
        businessRoleList.Cast<BusinessRole>().ToList().ForEach(delegate(BusinessRole currentRole)
        {

            DataGridViewRow currentRowForRole = dgvBusinessRole.Rows.Cast<DataGridViewRow>().ToList().Find(row => ((BusinessRole)row.DataBoundItem).Id == currentRole.Id);

            // Get a reference to the comboBox cell in the current row
            DataGridViewComboBoxCell comboBoxCell = (DataGridViewComboBoxCell)currentRowForRole.Cells[2];

            // Not sure if this is necessary since these properties should be inherited from the combobox column properties
            comboBoxCell.DisplayMember = "Name";
            comboBoxCell.ValueMember = "Id";
            comboBoxCell.ValueType = typeof(Guid);

            // Get the business area for the current business role
            BusinessArea currentAreaForRole = businessAreaRepository.FetchByRoleId(currentRole.Id);

            // if the role has an associated area then set the value of the cell to be the appropriate item in the combobox
            // and update the cell value
            if (currentAreaForRole != null)
            {

                foreach (BusinessArea area in comboBoxCell.Items)
                {
                    if (currentAreaForRole.Id == area.Id)
                    {
                        comboBoxCell.Value = area.Id;
                        dgvBusinessRole.UpdateCellValue(2, comboBoxCell.RowIndex);
                    }

                }

            }

        });
    }

The dgv is first bound to a binding list holding BusinessRole objects, then the combobox column is bound to a basic list of BusinessArea objects that come out of a repository class. I then loop through the bindinglist and pull out the row of the dgv that is bound to the current item in the bindinglist loop. With that row I make a database call to see if the BusinessRole entity is associated with a BusinessArea entity. If it is then I want to select the item in the combobox column that holds the BusinessAreas.

The problem is that when the grid is loaded, all the data is there and the comboboxes are populated with a list of available areas, however any values that are set are not displayed. The code that sets the value is definately getting hit and the value I am setting definately exists in the list.

There are no data errors, nothing. It's just refusing to update the UI with the value I programmatically set.

Any help would be greatly appreciated as always.

Thanks

I'm having this exact same problem! I'll keep trying things and reading around, and if I find anything I'll post it here! — Chris Stauffer, Feb 20 '13 at 19:06

James Richards · Answer 1 · 2013-03-01T16:27:24.343

This code works for my first combo box I have in my row with the following code, but I try it with the next one in the row and it doesn't work. I could use the help with the rest I have 3 more to do. I do set the combo boxes on a second form from this form with the same code as is on the last line of the try block but using the cell information instead of the dataset

 try
      {

          string strQuery = "select fundCode from vwDefaultItems where IncomeType = '" + stIncome + "'";

          SqlDataAdapter daDefault = new SqlDataAdapter(strQuery, conn);

          DataSet dsDefault = new DataSet();
          daDefault.Fill(dsDefault);
          strDefFund = dsDefault.Tables[0].Rows[0].ItemArray[0].ToString();
          dgvCheckEntry.Rows[curRow].Cells[7].Value = dsDefault.Tables[0].Rows[0].ItemArray[0].ToString();


      }
      catch (Exception eq)
      {

      }

DataGridViewComboBoxCell Value Not Updating When Set Programmatically C# Winforms

1 Answers1