Checking Nulls

[Atley]

Before I could just check for null, no matter what the variable type. How
do I check for null in different variable types such as Double, DateTime,
and Integer?

Any help is greatly appreciated.

Atley

 

[Chris Tacke, eMVP]

if(myvar == null) won't work for you?

 

[Atley]

I am using VB.NET 2003

@

if(myvar == null) won't work for you?

 

[Chris Tacke, eMVP]

Ok, the check against Nothing

If myvar = Nothing Then ....

 

[Geoff Schwab [MSFT]]

I am not sure what you are trying to do exactly, but does using Nothing work
for you?

Dim temp1 As Integer
If (temp1 = Nothing) Then
MessageBox.Show("Nothing")
End If

Dim temp2 As Double
If (temp2 = Nothing) Then
MessageBox.Show("Nothing")
End If

--
Geoff Schwab
Program Manager
Excell Data Corporation
http://msdn.com/mobility
http://msdn.microsoft.com/mobility/prodtechinfo/devtools/netcf/FAQ/default.aspx

This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Alex Feinman [MVP]]

That's Nothing in VB
If you are testing a primitive type (Integer, Double etc), you can use
IF val = Nothing Then
With objects it would be
If myObj Is Nothing Then

A problem here is that technically when you compare a primitive type to
Nothing it gets converted to an Object, so the result of this comparison is
not exactly what you want, but in most cases it will be.

 

[Roberto M. Oliva]

I use

if (myvar is nothing) = False Then
' myvar is declared
Else
' myvar points to nothing
End if

Roberto