How to compare only month and year? [VB]

Question

Its quite simple, i just want to compare two dates using month and year, if the input date (mont and year only) are above or below that current date (month and year).

Th

Answer 1

Using date values is probably best, but if string comparisons must be made.

Dim dDate as DateTime

If Not (DateTime.TryParse(txtBox.Text, dDate)) Then
  MessageBox.Show("check date.")
Else
  txtBox.Text = dDate.ToString("yyyyMM")
End If

If dDate.ToString("yyyyMM") < DateTime.Now.ToString("yyyyMM") Then
  MessageBox.Show("Below") 
ElseIf dDate.ToString("yyyyMM") > DateTime.Now.ToString("yyyyMM") Then
  MessageBox.Show("Above")
Else
  MessageBox.Show("Same")
End If

Answer 2

I'd avoid using strings.

    Dim dDate As DateTime
    If Not (DateTime.TryParse(txtBox.Text, dDate)) Then
        'bad date
        MessageBox.Show("check date.")
    Else
        Select Case dDate.Year
            Case Is < DateTime.Now.Year
                MessageBox.Show("Below")
            Case Is > DateTime.Now.Year
                MessageBox.Show("Above")

            Case Else 'years are equal,check month
                Select Case dDate.Month
                    Case Is < DateTime.Now.Month
                        MessageBox.Show("Below")
                    Case Is > DateTime.Now.Month
                        MessageBox.Show("Above")
                    Case Else 'equal months
                        MessageBox.Show("SAME") '????
                End Select
        End Select
    End If

Answer 3

Thank you everyone, but the final solutions is made with

If (dDate.Year < DateTime.Now.Year Or (dDate.Year = DateTime.Now.Year And dDate.Month < DateTime.Now.Month)) Then
  'something                
 Else
  'something
End If

Answer 4

Convert the year and month to Integer values, which are easy to compare less-than or greater-than. For example, if you had two DateTimePicker controls on a form, named dtpDate1 and dptDate2, and a button btnTest:

Private Sub btnTest_Click(sender As Object, e As EventArgs) Handles btnTest.Click

    Dim date1 As Integer = (dtpDate1.Value.Year * 100) + dtpDate1.Value.Month
    Dim date2 As Integer = (dtpDate2.Value.Year * 100) + dtpDate2.Value.Month

    MsgBox("Date1 = " & date1.ToString & vbCrLf & "Date2 = " & date2.ToString)

    If date1 = date2 Then MsgBox("Equal!")
    If date1 < date2 Then MsgBox("date1 is less than date2")
    If date1 > date2 Then MsgBox("date1 is greater than date2")

End Sub

The dates are converted to integers in a YYYYMM format. This is a data warehouse technique to convert dates to integers for better query performance when date is used often in a WHERE clause.