Dim Table As New DataTable
    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        Table.Columns.Add("Operación", Type.GetType("System.String"))
        Table.Columns.Add("Fecha Inicial", Type.GetType("System.DateTime"))
        Table.Columns.Add("Fecha Final", Type.GetType("System.DateTime"))

        DataGridView1.DataSource = Table

        For C As Integer = 0 To DataGridView1.Columns.Count - 1
            DataGridView1.Columns(C).HeaderCell.Style.Font = New Font("Microsoft Sans Serif", 10, FontStyle.Bold)
            DataGridView1.Columns(C).AutoSizeMode = DataGridViewAutoSizeColumnMode.AllCells
        Next C

End Sub

 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim date1 As Date
        Try   ' En el caso de error en TextBox1
            date1 = CType(TextBox1.Text, Date)
        Catch
            Exit Sub
        End Try

        Dim numRows As Integer
        Dim DateBegin As Date
        Dim DateEnd As Date
        Dim Duration As Integer

        '----------------CHANNEL
        Table.Rows.Add("CHANNEL")
        If Integer.TryParse(TextBox4.Text, numRows) Then
            If (numRows >= 1) Then
                For i As Integer = 1 To numRows

                    Duration = 1   ' Duración de esta actividad
                    DateBegin = NoWeekEnd(date1) ' El mismo dia de inicio   ' Comienza este trabajo
                    DateEnd = NoWeekEnd(DateBegin.AddDays(Duration))
                    Table.Rows.Add("TRACE AND CUT PLATE C" & i, DateBegin, DateEnd)
                    Next
        End If

     '----------------ENGINEERING
        Table.Rows.Add("ENGINEERING")
        Duration = TextBox2.Text
        DateBegin = NoWeekEnd(date1)
        DateEnd = NoWeekEnd(DateBegin.AddDays(Duration))
        Table.Rows.Add("SENDING DRAWINGS FOR APPROVAL", DateBegin, DateEnd)
        date1 = DateEnd
End Sub