How to check is null value in the table?

Question

USING MS ACCESS 2003

How to check is null value in the access database?

My code.

Public Function DateToString(dte As Date) As String
Dim d As String
Dim m As String
Dim y As String
d = Day(dte)
m = Month(dte)
y = Year(dte)
If Len(d) = 1 Then d = "0" & d
If Len(m) = 1 Then m = "0" & m
DateToString = y & m & d
End Function


Public Function StringToDate(txt As String) As Date
Dim dte As String
dte = Left(txt, 4) & "-" & Mid(txt, 5, 2) & "-" & Right(txt, 2)
StringToDate = CDate(dte)
End Function




sql1 = "CREATE TABLE MOI (PreDate varchar(50))"
sql2 = "INSERT INTO MOI values('" & StringToDate(rsCardEvent1.Fields("PreDate"))  "')"

From the above function, I want to check if not null then my code else no need.

Need VB 6.0 Code Help?

Answer 1

If the item is actually coming is as a string, then do:

if not txt is vbNullString then
    ' code here
end if

Answer 2

To check for Null in a dataset field:

If IsNull(rs("colname")) Then 
  'Field contains a Null Value 
Else 
  'Field does 'not' contain a Null Value 
End If

To check for null or Empty string:

If (txt & "") = "" Then 
  ' txt is Null or empty
End If