Html calendar

Diy html calendar.vb

Partial Class Calendar
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
        If Not IsPostBack Then
            RenderCalendar()
        End If
    End Sub

    Sub RenderCalendar()
        Dim calendar = New StringBuilder()

        Dim startDate As New DateTime(2015, 8, 2)
        Dim endDate As New DateTime(2015, 8, 8)
        Dim [date] As DateTime = startDate
        calendar.AppendFormat("{0}<div class=""week weekHeading clearfix"">{0}", vbCrLf)
        While [date] <= endDate
            Dim dw As DayOfWeek = [date].DayOfWeek
            [date] = [date].AddDays(1)
            calendar.AppendFormat("{1}<div class=""dayOfWeek dayOfWeek{2}"">{0}</div>{1}", dw.ToString(), vbCrLf, CInt(dw) + 1)
        End While
        calendar.AppendFormat("{0}</div><!-- End Week -->{0}", vbCrLf)

        Dim year = 2015
        Dim month = 7

        'DateTime.DaysInMonth(year, month)
        Dim firstDay = New DateTime(year, month, 1)
        Dim dayOfWeek = CInt(firstDay.DayOfWeek)

        calendar.AppendFormat("{0}<div class=""week clearfix"">{0}", vbCrLf)
        For i = 0 To dayOfWeek - 1
            calendar.AppendFormat("{0}<div class=""day empty""></div>{0}", vbCrLf)
        Next

        Dim totalDaysInMonth = DateTime.DaysInMonth(year, month)
        For i As Integer = 1 To totalDaysInMonth
            Dim day = New DateTime(year, month, i)

            If day.DayOfWeek = System.DayOfWeek.Sunday Then
                calendar.AppendFormat("{0}<div class=""week clearfix"">{0}", vbCrLf)
            End If

            'lastDayOfWeekOfMonth
            If totalDaysInMonth = day.Day Then
                calendar.AppendFormat("{1}<div class=""day dayOfWeek{2} lastDayOfMonth""><span class=""dayNumber"">{0}</span></div>{1}", i, vbCrLf, CInt(day.DayOfWeek) + 1)
            ElseIf day.AddDays(7).Month <> day.Month Then
                calendar.AppendFormat("{1}<div class=""day dayOfWeek{2} lastDayOfWeekOfMonth""><span class=""dayNumber"">{0}</span></div>{1}", i, vbCrLf, CInt(day.DayOfWeek) + 1)
            Else
                calendar.AppendFormat("{1}<div class=""day dayOfWeek{2}""><span class=""dayNumber"">{0}</span></div>{1}", i, vbCrLf, CInt(day.DayOfWeek) + 1)
            End If


            If day.DayOfWeek = System.DayOfWeek.Saturday Then
                calendar.AppendFormat("{0}</div><!-- End Week -->{0}", vbCrLf)
            End If
        Next

        litCalendar.Text = calendar.ToString()
    End Sub
End Class