How to Calculate Two Columns in DataGridView

In my previous tutorial using DataGridView Control I explained on “How to Differentiate Two Cell Values in DataGridView Control”. This time I will teach you on how to calculate two columns in DataGridView Control.

This tutorial is very useful if you want to make a total of the two columns. For example a total of “Qty” and “Sales Price” Column.

Additionally, we will make a total of the “Amount” column.

To achieve this all you have to do is trigger the CellEndEdit Events.

 Private Sub InvoiceDetailsDataGridView_CellEndEdit(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles InvoiceDetailsDataGridView.CellEndEdit
  Dim InvoiceDetails As DataGridView = DirectCast(sender, DataGridView)
 
  If IsDBNull(InvoiceDetails(0, e.RowIndex).Value) Then Exit Sub
 
  InvoiceDetails("Amount", e.RowIndex).Value = InvoiceDetails("Qty", e.RowIndex).Value * InvoiceDetails("SalesPrice", e.RowIndex).Value
 
  If (e.ColumnIndex = 2 Or e.ColumnIndex = 4) And InvoiceDetails.Rows.Count > 0 Then
  TotalTextBox.Text = Total().ToString
  End If
  End Sub 

This assume that the name of your DataGridView Control is InvoiceDetailsDataGridView and you have change the name of the column to “Qty”, “SalesPrice”, and “Amount”.

[inline:datagridview_columns_properties.jpg=DataGridView Column Properties]

 e.ColumnIndex = 2 Or e.ColumnIndex = 4 assumes that “Qty” column has an index equals to 2 and “Amount” equals to 4.

Now here’s the Total function.

 Private Function Total() As Double
  Dim tot As Double = 0
  Dim i As Integer = 0
 
  For i = 0 To InvoiceDetailsDataGridView.Rows.Count - 1
  tot = tot + Convert.ToDouble(InvoiceDetailsDataGridView.Rows(i).Cells("Amount").Value)
  Next i
 
  Return tot
  End Function 

What you need here is a DataGridView Control and a TextBox named “TotalTextBox”.