IsNull

[Bryan]

I am having trouble using the IsNull() function in VB.net. Here the line of code:

If Not IsNull(TextBox1.Text) Then
End If

it tells me that IsNull is not declared, do I have to use an inherits system.??? to be able to use the IsNull() function?

 

[PlausiblyDamp]

If you are checking if the textbox is empty you can check for an empty string

if TextBox1.Text <> String.Empty Then

End IF

If you are checking if a variable is null the nunder vb check for nothing

dim o as object
if o is nothing then

end if

 

[georgepatotk]

If Not TextBox1.Text IS system.dbnull.value Then
End If

 

[Bryan]

If you are checking if the textbox is empty you can check for an empty string

if TextBox1.Text <> String.Empty Then

End IF

If you are checking if a variable is null the nunder vb check for nothing

dim o as object
if o is nothing then

end if

yes, but what about the IsNull function. Id like to use that, ive used it before, but its been a while and Id like to know how to use it.

 

[PlausiblyDamp]

IIRC IsNull is no longer supported in VB.Net - the nearest equivalent is DbNull as georgepatotk suggested in the post above.