84.txt

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Increment and decrement dates with the [+] and [-] keys
By Mike Coleman, [e-mail]
If you注释：ve ever used Quicken, you注释：ve probably noticed a handy little feature in that program注释：s date fields. You can press the [+] key to increment one day, [-] to decrement one day, [PgUp] to increment one month, and [PgDn] to decrement one month. In this tip, we注释：ll show you how to emulate this behavior with Visual Basic. 

First, insert a text box on a form (txtDate). Set its text property to "" and its Locked property to TRUE. 

Now place the following code in the KeyDown event: 

Private Sub txtDate_KeyDown(KeyCode As Integer, Shift As Integer)
注释：
注释： 107 = "+" KeyPad
注释： 109 = "-" KeyPad
注释： 187 = "+" (Actually this is the "=" key, same as "+" w/o the shift)
注释： 189 = "-"
注释： 33 = PgUp
注释： 34 = PgDn
注释：
Dim strYear As String
Dim strMonth As String
Dim strDay As String
注释：
If txtDate.Text = "" Then
  txtDate.Text = Format(Now, "m/d/yyyy")
  Exit Sub
End If
注释：
strYear = Format(txtDate.Text, "yyyy")
strMonth = Format(txtDate.Text, "mm")
strDay = Format(txtDate.Text, "dd")
注释：
Select Case KeyCode
  Case 107, 187 注释： add a day
    txtDate.Text = Format(DateSerial(strYear, strMonth, strDay) + 1, "m/d/yyyy")
  Case 109, 189 注释： sbutract a day
    txtDate.Text = Format(DateSerial(strYear, strMonth, strDay) - 1, "m/d/yyyy")
  Case 33 注释： add a month
    txtDate.Text = Format(DateSerial(strYear, strMonth + 1, strDay), "m/d/yyyy")
  Case 34 注释： subtract a month
    txtDate.Text = Format(DateSerial(strYear, strMonth - 1, strDay), "m/d/yyyy")
End Select
注释：
End Sub 

The one nasty thing about this is that if you have characters that are not the characters usually in a date (i.e., 1-9, Monday, Tuesday, or /) you get errors in the format command. To overcome this, I set the Locked property to True. This way, the user can注释：t actually type a character in the field, but the KeyDown event still fires.