Reseting a variable intOldDate As Date to null

[RobH]

I need to reset a variable inOldDate which was set as a Date back to null.

In my module1 if have
Public intOldDate As Date

I have a form with a field (AppoinmentDate) which on gotfocus copies the current value of AppointmentDate to the variabe intOldDate the form has a submit button (save) that compares the difference between intOldDate and the value when the save button is pressed. If the value is different then the currentdate gets written to another field - DateAppointmentSet

The problem I have is that the first time they do this its fine. The second time through the previous value remains in intOldDate - I need to be able to reset the variable to Null or whatever the default value should be.

[cyberdwarf]

Setting the date variable = 0 will give you a date of 30/12/1899. This will probably be OK for most purposes, provided you use the correct comparison value.

Setting a date to Empty gives you the uninitialised value 00:00:00 (This is my preferred method). You can check for this by using

Dim DateVar As Date
DateVar = Empty
If DateVar = "00:00:00" Then
     debug.print "Empty"
Else
     debug.print DateVar
End If

You can set the date to a negative number, if you wish

HTH

Steve

[RobH]

Setting the date variable = 0 will give you a date of 30/12/1899. This will probably be OK for most purposes, provided you use the correct comparison value.

Setting a date to Empty gives you the uninitialised value 00:00:00 (This is my preferred method). You can check for this by using

Dim DateVar As Date
DateVar = Empty
If DateVar = "00:00:00" Then
     debug.print "Empty"
Else
     debug.print DateVar
End If

You can set the date to a negative number, if you wish

HTH

Steve

I sort of came to my own version of this same process by setting the variable to a known Variable date of 1/1/2000 and as you indicated I check against that.

Probably not as pretty and Industry standardised as the solution you have provided - but thanks