Trabalhando com DataGridView!

Bom dia!

Alguem poderia me ajudar a converter esse código de VB para C#. Tentei converter, mas na hora de compilar, aparece alguns erros de código. Esse código é sobre teclas de atalho para movimentar as linhas de um datagridview. Igual o mecanismo da barra de rolagem, mas usando teclas. PageUp, PageDown, Top, Up...

Private Sub swapRows(ByVal range As mode)
Dim iSelectedRow As Integer = -1
For iTmp As Integer = 0 To Datagridview.Rows.Count - 1
If Datagridview.Rows(iTmp).Selected Then
iSelectedRow = iTmp
Exit For
End If
Next

If iSelectedRow <> -1 Then
Dim sTmp(4) As String
For iTmp As Integer = 0 To Datagridview.Columns.Count - 1
sTmp(iTmp) = Datagridview.Rows(iSelectedRow).Cells(iTmp).Value.ToString
Next

Dim iNewRow As Integer
If range = mode.down Then
iNewRow = iSelectedRow + 1
ElseIf range = mode.up Then
iNewRow = iSelectedRow - 1
End If

If range = mode.up Or range = mode.down Then
For iTmp As Integer = 0 To Datagridview.Columns.Count - 1
Datagridview.Rows(iSelectedRow).Cells(iTmp).Value = Datagridview.Rows(iNewRow).Cells(iTmp).Value
Datagridview.Rows(iNewRow).Cells(iTmp).Value = sTmp(iTmp)
Next
toSelect(iNewRow)
ElseIf range = mode.top Or range = mode.bottom Then
reshuffleRows(sTmp, iSelectedRow, range)
End If
End If
End Sub

Private Sub toSelect(ByVal iNewRow As Integer)
Datagridview.Rows(iNewRow).Selected = True
End Sub

Private Sub reshuffleRows(ByVal sTmp() As String, ByVal iSelectedRow As Integer, ByVal Range As mode)
If Range = mode.top Then
Dim iFirstRow As Integer = 0
If iSelectedRow > iFirstRow Then
For iTmp As Integer = iSelectedRow To 1 Step -1
For iCol As Integer = 0 To Datagridview.Columns.Count - 1
Datagridview.Rows(iTmp).Cells(iCol).Value = Datagridview.Rows(iTmp - 1).Cells(iCol).Value
Next
Next
For iCol As Integer = 0 To Datagridview.Columns.Count - 1
Datagridview.Rows(iFirstRow).Cells(iCol).Value = sTmp(iCol).ToString
Next
toSelect(iFirstRow)
End If
Else
Dim iLastRow As Integer = Datagridview.Rows.Count - 1
If iSelectedRow < iLastRow Then
For iTmp As Integer = iSelectedRow To iLastRow - 1
For iCol As Integer = 0 To Datagridview.Columns.Count - 1
Datagridview.Rows(iTmp).Cells(iCol).Value = Datagridview.Rows(iTmp + 1).Cells(iCol).Value
Next
Next
For iCol As Integer = 0 To Datagridview.Columns.Count - 1
Datagridview.Rows(iLastRow).Cells(iCol).Value = sTmp(iCol).ToString
Next
toSelect(iLastRow)
End If
End If
End SubDesde já agradeço pela ajuda e atenção...Muito Obrigado...