Vfrdtyky

I am building a table using the DataGridView where a user can select items from a dropdown in each cell. To simplify the problem, lets say i have 1 column. I am using the DataGridViewComboBoxColumn in the designer. I am trying to support having each row in that column have a different list of items to choose from.

Is this possible?

Yes. This can be done using the DataGridViewComboBoxCell.

Here is an example method to add the items to just one cell, rather than the whole column.

private void setCellComboBoxItems(DataGridView dataGrid, int rowIndex, int colIndex, object itemsToAdd)

{

    DataGridViewComboBoxCell dgvcbc = (DataGridViewComboBoxCell) dataGrid.Rows[rowIndex].Cells[colIndex];

    // You might pass a boolean to determine whether to clear or not.

    dgvcbc.Items.Clear();

    foreach (object itemToAdd in itemsToAdd)

    {

        dgvcbc.Items.Add(itemToAdd);

    }

}

private void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)

{

    if (e.ColumnIndex == DataGridViewComboBoxColumnNumber)

    {

        setCellComboBoxItems(myDataGridView, e.RowIndex, e.ColumnIndex, someObj);

    }

}

Just in case anyone finds this thread, this is my solution in VB 2008. The advantage this offers is that it allows you to assign an ID to each value in the combobox.

  Private Sub FillGroups()

    Try

        'Create Connection and SQLCommand here.



        Conn.Open()

        Dim dr As SqlDataReader = cm.ExecuteReader



        dgvGroups.Rows.Clear()



        Dim PreviousGroup As String = ""



        Dim l As New List(Of Groups)



        While dr.Read



            Dim g As New Groups

            g.RegionID = CheckInt(dr("cg_id"))

            g.RegionName = CheckString(dr("cg_name"))

            g.GroupID = CheckInt(dr("vg_id"))

            g.GroupName = CheckString(dr("vg_name"))

            l.Add(g)



        End While

        dr.Close()

        Conn.Close()



        For Each a In (From r In l Select r.RegionName, r.RegionID).Distinct



            Dim RegionID As Integer = a.RegionID 'Doing it this way avoids a warning



            dgvGroups.Rows.Add(New Object() {a.RegionID, a.RegionName})



            Dim c As DataGridViewComboBoxCell = CType(dgvGroups.Rows(dgvGroups.RowCount - 1).Cells(colGroup.Index), DataGridViewComboBoxCell)

            c.DataSource = (From g In l Where g.RegionID = RegionID Select g.GroupID, g.GroupName).ToArray

            c.DisplayMember = "GroupName"

            c.ValueMember = "GroupID"

        Next



    Catch ex As Exception

    End Try

End Sub



Private Class Groups



    Private _RegionID As Integer

    Public Property RegionID() As Integer

        Get

            Return _RegionID

        End Get

        Set(ByVal value As Integer)

            _RegionID = value

        End Set

    End Property



    Private _RegionName As String

    Public Property RegionName() As String

        Get

            Return _RegionName

        End Get

        Set(ByVal value As String)

            _RegionName = value

        End Set

    End Property



    Private _GroupName As String

    Public Property GroupName() As String

        Get

            Return _GroupName

        End Get

        Set(ByVal value As String)

            _GroupName = value

        End Set

    End Property



    Private _GroupID As Integer

    Public Property GroupID() As Integer

        Get            

            Return _GroupID

        End Get

        Set(ByVal value As Integer)

            _GroupID = value

        End Set

    End Property



End Class

this is an example with gridView which have 2 comboboxColumns and when a comboBoxColumns1 selected index changed then load comboBoxColumns2 with data from from two different columns from database .

 private void dataGridView1_CellEndEdit(object sender, DataGridViewCellEventArgs e)

        {

              if (dataGridView1.Rows[e.RowIndex].Cells[0].Value != null && dataGridView1.CurrentCell.ColumnIndex == 0)

            {



                SqlConnection conn = new SqlConnection("data source=.;initial catalog=pharmacy;integrated security=true");

                SqlCommand cmd = new SqlCommand("select [drugTypeParent],[drugTypeChild] from [drugs] where [drugName]='" + dataGridView1.Rows[e.RowIndex].Cells[0].Value.ToString() + "'", conn);

                conn.Open();

                SqlDataReader dr = cmd.ExecuteReader();

                while (dr.Read())

                {



                    object o = new object { dr[0].ToString(),dr[1].ToString() };

                    DataGridViewComboBoxCell dgvcbc = (DataGridViewComboBoxCell)dataGridView1.Rows[e.RowIndex].Cells[1];



                    dgvcbc.Items.Clear();

                    foreach (object itemToAdd in o)

                    {

                        dgvcbc.Items.Add(itemToAdd);

                    }

                }

                dr.Close();

                conn.Close();

               }

            }

setting the comboboxcell right after setting datasource doesnt work for me. it has to be done after binding operations completed. i choosed CellBeginEdit

example of empty dropdowns:

dgv1.datasource = datatable1;

dgv1.columns.add ( "cbxcol"  , typeof(string) );



//  different source for each comboboxcell in rows

var dict_rowInd_cbxDs = new Dictionary<int, object>();

dict_rowInd_cbxDs[1] = new list<string>(){"en" , "us"};

dict_rowInd_cbxDs[2] = new list<string>(){ "car", "bike"};



// !!!!!! setting comboboxcell after creating doesnt work here

foreach( row in dgv.Rows.asEnumerable() )

{ 

   var cell = res_tn.dgv.CurrentCell as DataGridViewComboBoxCell;

   cell.DataSource = dict_dgvRowI_cbxDs[res_tn.dgv.CurrentCell.RowIndex];



}

working example:

dgv1.datasource = datatable1;

dgv1.columns.add ( "cbxcol"  , typeof(string) );



//  different source for each comboboxcell in rows

var dict_rowInd_cbxDs = new Dictionary<int, object>();

dict_rowInd_cbxDs[1] = new list<string>(){"en" , "us"};

dict_rowInd_cbxDs[2] = new list<string>(){ "car", "bike"};





// cmboboxcell datasource Assingment Must be done after  BindingComplete (not tested )  or cellbeginEdit  (tested by me)    

res_tn.dgv.CellBeginEdit += (s1, e1) => {

    if (res_tn.dgv.CurrentCell is DataGridViewComboBoxCell) {

        if (dict_dgvRowI_cbxDs.ContainsKey(res_tn.dgv.CurrentCell.RowIndex)) 

        {

            var cll = res_tn.dgv.CurrentCell as DataGridViewComboBoxCell;

            cll.DataSource = dict_dgvRowI_cbxDs[res_tn.dgv.CurrentCell.RowIndex];



           // required if it is  list<mycustomClass>

           // cll.DisplayMember = "ColName";

           // cll.ValueMember = "This";

        }

    }



};

    //Populate the Datatable with the Lookup lists

    private DataTable typeDataTable(DataGridView dataGridView, Lookup<string, Element> type_Lookup, Dictionary<Element, string> type_dictionary, string strNewStyle, string strOldStyle, string strID, string strCount)

    {

        int row = 0;



        DataTable dt = new DataTable();



        dt.Columns.Add(strOldStyle, typeof(string));

        dt.Columns.Add(strID, typeof(string));

        dt.Columns.Add(strCount, typeof(int));

        dt.Columns.Add("combobox", typeof(DataGridViewComboBoxCell));







        //Add All Doc Types to ComboBoxes

        DataGridViewComboBoxCell CmBx = new DataGridViewComboBoxCell();

        CmBx.DataSource = new BindingSource(type_dictionary, null);

        CmBx.DisplayMember = "Value";

        CmBx.ValueMember = "Key";





        //Add Style Comboboxes

        DataGridViewComboBoxColumn Data_CmBx_Col = new DataGridViewComboBoxColumn();

        Data_CmBx_Col.HeaderText = strNewStyle;

        dataGridView.Columns.Add(addDataGrdViewComboBox(Data_CmBx_Col, type_dictionary));



        setCellComboBoxItems(dataGridView, 1, 3, CmBx);



        //Add style Rows

        foreach (IGrouping<string, Element> StyleGroup in type_Lookup)

        {

            row++;

            //Iterate through each group in the Igrouping

            //Add Style Rows

            dt.Rows.Add(StyleGroup.Key, row, StyleGroup.Count().ToString());





        }

        return dt;

    }









    private void setCellComboBoxItems(DataGridView dataGrid, int rowIndex, int colIndex, DataGridViewComboBoxCell CmBx)

    {

        DataGridViewComboBoxCell dgvcbc = (DataGridViewComboBoxCell)dataGrid.Rows[rowIndex].Cells[colIndex];

        // You might pass a boolean to determine whether to clear or not.

        dgvcbc.Items.Clear();

        foreach (DataGridViewComboBoxCell itemToAdd in CmBx.Items)

        {

            dgvcbc.Items.Add(itemToAdd);

        }