Code Block
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim dt As New DataTable
dt.Columns.Add("income", GetType(System.Int32))
dt.Columns.Add("income1", GetType(System.Int32))
dt.Columns.Add("sum", GetType(System.Int32))
dt.Rows.Add(500, 200)
dt.Rows.Add(0, 100)
dt.Rows.Add(200, 100)
Me.DataGridView1.DataSource = dt
End Sub
Private Sub DataGridView1_CellValidated(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellValidated
Dim sum As Int32 = 0
For Each r As DataGridViewRow In Me.DataGridView1.Rows
sum = sum + r.Cells(0).Value - r.Cells(1).Value
r.Cells(2).Value = sum
Next
End Sub
End Class