Is there a problem with IIF or am I doing something wrong?

[Charles May]

I have a listview which checkboxes containing items to invoice. The Create
Invoice button (button1) is disabled unless there are items checked.
However, I had to use an if..then..else statement to make it work. My
question is, why can I not get it to work using an IIF statement?

In the mouseup event of the listview I tried the following methods to
achieve the result.
This doesn't work
IIF(Listview1.CheckedItems.Count > 0, Button1.Enabled = True,
Button1.Enabled = False)

This works

If Listview1.CheckedItems.Count > 0 Then
Button1.Enabled = True
Else
Button1.Enabled = False
End If

I'm just curious if I did something wrong trying to use IIF instead of
IF...THEN...ELSE

Thanks

Charlie

[Mattias Sjögren]

Charles,

I'm just curious if I did something wrong trying to use IIF instead of
IF...THEN...ELSE

IIF is not a built-in language statement, it's a function. And like
any other function, all the parameters you pass to it are evaluated,
and using = in that context performs comparison, not assignment.

Mattias

--
Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

[Jay B. Harlow [MVP - Outlook]]

Charles,
In addition to Mattias's comments, have you considered simply using:

Button1.Enabled = (Listview1.CheckedItems.Count > 0)

Hope this helps
Jay

"Charles May" <qu*********@hotmail.com> wrote in message
news:yB4Fb.101864$8y1.312337@attbi_s52...

I have a listview which checkboxes containing items to invoice. The Create
Invoice button (button1) is disabled unless there are items checked.
However, I had to use an if..then..else statement to make it work. My
question is, why can I not get it to work using an IIF statement?

In the mouseup event of the listview I tried the following methods to
achieve the result.
This doesn't work
IIF(Listview1.CheckedItems.Count > 0, Button1.Enabled = True,
Button1.Enabled = False)

This works

If Listview1.CheckedItems.Count > 0 Then
Button1.Enabled = True
Else
Button1.Enabled = False
End If

I'm just curious if I did something wrong trying to use IIF instead of
IF...THEN...ELSE

Thanks

Charlie

[Charles May]

Thanks Mattias.

It's working now with your help

Charlie
"Mattias Sjögren" <ma********************@mvps.org> wrote in message
news:%2****************@tk2msftngp13.phx.gbl...

Charles,

I'm just curious if I did something wrong trying to use IIF instead of
IF...THEN...ELSE

IIF is not a built-in language statement, it's a function. And like
any other function, all the parameters you pass to it are evaluated,
and using = in that context performs comparison, not assignment.

Mattias

--
Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.