How To Determine the New Month Selected in Calendar Control

MORE INFORMATION

The Microsoft Calendar control does not ship with Visual Basic. The control ships as part of Microsoft Access or may be downloaded for free from the following URL:

Step-by-Step Example

1. Start Visual Basic and create a new Standard EXE project. Form1 is created by default.
2. On the Project menu, click Components, and then check the "Microsoft Calendar Control 8.0" component. The Calendar control is made available on the Toolbox.
3. Put a Calendar control on Form1.
4. Copy and paste the following code to the form's code window:

         Option Explicit
         Private Declare Function FindWindowEx Lib "user32" _
            Alias "FindWindowExA" _
            (ByVal hWnd1 As Long, _
            ByVal hWnd2 As Long, _
            ByVal lpsz1 As String, _
            ByVal lpsz2 As String) As Long
   
         Private Declare Function SendMessage Lib "user32" _
            Alias "SendMessageA" _
            (ByVal hwnd As Long, _
            ByVal wMsg As Long, _
            ByVal wParam As Long, _
            lParam As Any) As Long
   
         Private Const CB_GETCURSEL = &H147
         Private Const CB_GETLBTEXT = &H148
         Private calendarHwnd As Long
         Private cboMonthHwnd As Long
         Private cboYearHwnd As Long
   
         Private Sub Form_Load()
            calendarHwnd = FindWindowEx(Me.hwnd, 0&, "CalendarWndClass", _
               vbNullString)
            cboMonthHwnd = FindWindowEx(calendarHwnd, 0&, "ComboBox", _
               vbNullString)
          cboYearHwnd = FindWindowEx(calendarHwnd, cboMonthHwnd, "ComboBox", _
               vbNullString)
         End Sub
   
         Private Sub Calendar1_NewMonth()
            Dim monthIndex As Long, temp As Long
            Dim ret As String * 255
            ret = Space(255)
            ' Find 0-based index of the selected item:
            monthIndex = SendMessage(cboMonthHwnd, CB_GETCURSEL, 0&, 0&)
            ' Put month name in ret and length of month name in temp:
            temp = SendMessage(cboMonthHwnd, CB_GETLBTEXT, monthIndex, _
                ByVal ret)
            ' uncomment the line below to see if the ComboBox was used:
            'If Calendar1.Month = 0 Then Debug.Print "ComboBox used to
            'select";
            Debug.Print Left(ret, temp) 'Displays Month Name
         End Sub
   
         Private Sub Calendar1_NewYear()
            Dim yearIndex As Long, temp As Long
            Dim ret As String * 255
            ret = Space(255)
            ' Find 0-based index of the selected item:
            yearIndex = SendMessage(cboYearHwnd, CB_GETCURSEL, 0&, 0&)
            ' Put year value in ret and length of year value in temp:
            temp = SendMessage(cboYearHwnd, CB_GETLBTEXT, yearIndex, _
                ByVal ret)
            ' uncomment the line below to see if the ComboBox was used:
            'If Calendar1.Year = 0 Then Debug.Print "ComboBox used to
            'select ";
            Debug.Print Left(ret, temp) 'Displays Year
         End Sub
   						

5. Press the CTRL+G key combination to view the Immediate Window.
6. Press the F5 key to run the project.
7. Choose a month from the first combo box. Note the Immediate Window displays the month name selected.
8. Choose a year from the second combo box. Note the Immediate Window displays the year selected.

NOTE: The NewMonth event can occur either by using the ComboBox to select a new month or by clicking a new day that is in a different month than the one currently shown.

For example, suppose the current value in the Calendar is February 1. If you click on what would be the 31st day, the NewMonth event occurs because you have chosen a day in January. If you need to distinguish between using the ComboBox to select a month versus clicking a day in the calendar that changes the month, check the Month property of the calendar in the NewMonth event. If Month is 0, the ComboBox was used to select the new month. Otherwise, if Month is greater than 0, the user chooses a new date in the Calendar. Similarly, you can check the Year property in the NewYear event.