When the last row in a DataGridView is selected, a value from the previous row is returned instead of from the selected row - vb.net

Question

I have a DataGridView on a form which is populated by a dataset. Everything works except one thing. In the first column I have id numbers. The user clicks on some row, and the id number from the column is taken to be deleted from the db. Every id is taking correctly except the last row - it is a new row, as you know, because the user can create new records in the database. Anyhow, if the user makes a mistake and selects this row, my code shown below somehow gets the id number from the previous row. I don't know how to avoid that issue. I am taking it using this code:
dgv.CurrentRow.Cells(0).Value
Edit:
i've added code i am using to better understand the situation:
Form Load event:
Private Sub FrmNewRodzaj_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Dim del As DelegateGridRefresh = New DelegateGridRefresh(AddressOf FillGrid)
Dim del2 As DelegateGridRefresh = New DelegateGridRefresh(AddressOf AlignGrid)
del = [Delegate].Combine(del, del2)
AddHandler EventGridRefresh, AddressOf del.Invoke
del.Invoke()
End Sub
Fill Grid method:
Private Sub FillGrid()
NewRodzaj = New MachineRodzaj()
dgv.DataSource = NewRodzaj.GetRodzaje.Tables(0)
End Sub
GetRodzaje method:
Public Function GetRodzaje() As DataSet
Dim con As New SqlConnection(strcon)
Dim cmd As New SqlCommand("Select * from tbMachRodzajList", con)
con.Open()
GetRodzajeDataAdapter = New SqlDataAdapter(cmd)
GetRodzajeDataAdapter.Fill(GetRodzajeDataSet, "trial1")
Return GetRodzajeDataSet
End Function
AlignGrid method:
Private Sub AlignGrid()
dgv.RowsDefaultCellStyle.BackColor = Color.SkyBlue 'LightSkyBlue
dgv.AlternatingRowsDefaultCellStyle.BackColor = Color.LightBlue
dgv.ColumnHeadersBorderStyle = DataGridViewCellBorderStyle.None
dgv.AllowUserToAddRows = True
dgv.DefaultCellStyle.Font = New Font("Tahoma", 9)
Me.dgv.DefaultCellStyle.SelectionForeColor = Color.Red
Me.dgv.DefaultCellStyle.SelectionBackColor = Color.Yellow
Me.dgv.RowHeadersVisible = False
Dim column0 As DataGridViewColumn = dgv.Columns(0)
column0.Visible = False
Dim ColNazwa As DataGridViewColumn = dgv.Columns(1)
ColNazwa.HeaderText = "Nazwa"
ColNazwa.[ReadOnly] = False
Dim ColOpis As DataGridViewColumn = dgv.Columns(2)
ColOpis.HeaderText = "Opis"
ColOpis.[ReadOnly] = False
Dim column3 As DataGridViewColumn = dgv.Columns(3)
column3.Visible = False
dgv.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.Fill
Dim dgvColumnHeaderStyle As New DataGridViewCellStyle()
dgvColumnHeaderStyle.Alignment = DataGridViewContentAlignment.MiddleCenter
dgv.ColumnHeadersDefaultCellStyle = dgvColumnHeaderStyle
'You cannot change the column and row header colours without disabling visual styles:
dgv.EnableHeadersVisualStyles = False
' Set the row and column header styles.
dgv.ColumnHeadersDefaultCellStyle.ForeColor = Color.WhiteSmoke
dgv.ColumnHeadersDefaultCellStyle.BackColor = Color.Firebrick
dgv.ColumnHeadersDefaultCellStyle.Font = New Font("Tahoma", 14)
End Sub
button method to save/update data:
Private Sub btnSave_Click(sender As System.Object, e As System.EventArgs) Handles btnZapisz.Click
NewRodzaj.MakeChanges()
RaiseEvent EventGridRefresh()
End Sub
MakeChanges method:
Public Sub MakeChanges()
MachineRodzajDAO.GetRodzajeMakeChanges()
End Sub
GetRodzajeMakeChanges method:
Public Sub GetRodzajeMakeChanges()
If Not GetRodzajeDataSet.HasChanges Then
MessageBox.Show("No changes no need to update", "Informacja", MessageBoxButtons.OK, MessageBoxIcon.Information)
Else
Dim cmdbuilder As New SqlCommandBuilder(GetRodzajeDataAdapter)
Dim i As Integer
Try
i = GetRodzajeDataAdapter.Update(GetRodzajeDataSet, "trial1")
MsgBox("Updated" & i & " records")
Catch ex As Exception
MsgBox(ex.Message)
End Try
End If
End Sub
so the one is missing and i am fighting with is delete button after user select row to be deleted from db and click delete button, if he select newRow then message should appear - you selected wrong row. The id values are placed within column(0) when i use CurrentRow.Cells(0).Value if user click newRow then id is id of before row so i cannot just make check if value is nothing and also IsNewRow not working.
Private Sub btnDelete_Click(sender As System.Object, e As System.EventArgs) Handles btnUsun.Click
End Sub
Hope now will be clear enough

Answer 1

actually isNewRow works great
put it on Event dgv.CellClick for example
If dgv.CurrentRow.IsNewRow Then
'Cancel your code
Else
'Execute your code
End If
Edit: then check the row index like
dgv.NewRowIndex
that will always be the NewRowIndex
so if a user clicks a row or NewRow that row will become CurrentRow
you could then check stuff like
If dgv.CurrentRow.Index = dgv.NewRowIndex - 1 Then
'User clicked NewRow but CurrentRow is the one before the NewRow
End If
Edit: actually this is pretty straight forward
but you have to know what is happening on your DGV.
1.
user clicks NewRow and the ClickedCell just gets selected then u get the correct RowIndex with
dgv.SelectedCells(0).RowIndex
which is the same as
BenutzerDataGridView.NewRowIndex
and CurrentRow.Index will always be -1
User clicks NewRow and start typing. Now NewRow moves one Row down and the Row which is being edited becomes CurrentRow.
that's why i added the above to always ensure that it is not the NewRow
If dgv.CurrentRow.Index = dgv.NewRowIndex - 1 Then
this should actually be enough to do what you want ^^
last EDIT:
If dgv.SelectedCells(0).RowIndex = dgv.NewRowIndex Then
MsgBox("wrong row")
End If
or this way
If dgv.Rows(dgv.SelectedCells(0).RowIndex).IsNewRow Then
MsgBox("wrong row")
End If
i'm glad u got it sorted out ^^