We would like to compare a date from the db with current date.
Here is what I have tried so far:
'Obtain current date
Dim curdate As String = Now.ToString("yyyy")
'Now compare curdate with date from db called eventdate. Event date is of dateTime datatype.
If drv("eventdate").ToString = "" And Year(drv("eventdate").ToString) = curdate Then
'Then do some processing
End if
When I run this code, I get following error:
Conversion from string "" to type 'Date' is not valid.
Please help!
Thank you very much experts.
If Today.CompareTo(CDate(drv("eventdate")).Date) = 0 Then
'Do something
End If
I'm making the assumption here that you only care about the day, and not the time. Otherwise, the odds of having a match within a given day would be about 1 in 2.5 million.
Based on the comment:
If Today.Year.CompareTo(CDate(drv("eventdate")).Year) = 0 Then
'Do something
End If
or
If Today.Year = CDate(drv("eventdate")).Year Then
'Do something
End if
And one more thing: it really sounds like this is a check that should be done by your database . Make it part of the query that returns the results. This will be much faster, and it's where that kind of check belongs. All you'd need is add a check to your where clause like so:
Year(eventdate) = Year(current_timestamp)
If drv
has an instance of DataReader then verify DBNull
.
IF Not drv.IsDBNull(column_index_of_eventdate) Then
...
If drv.GetDateTime(column_index).Year=Date.Now.Year Then
...
End If
End If
I believe you have either a null or empty value, also your comparisn is wrong, try:
If drv("eventdate").ToString <> "" Andalso Year(drv("eventdate").ToString) = curdate Then
'Then do some processing
End if
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