Public Variable Scope

[scott]

I've got a public variable called "userID" declared in a module. When a user
logs into my app through a log in form, I'm setting the "userID" variable
equal to his userID field in a users table after he supplies a
user/password.

For some reason, the "userID" variable is null within my app.

Why would a public variable loose it's value between forms?


CODE*********
Public userID As Integer

 

[Larry Linson]

Public variables can lose their values if you encounter an error and do not
handle it. That may or may not be what you are experiencing. Have you put a
stop in the code just after you think you are setting the variable? Then,
use the immediate window to examine the value of the variable.

A public Variable in a standard Module, in the absence of unhandled errors,
should retain the value, if it was set.

Larry Linson
Microsoft Access MVP

 

[scott]

I changed the "userID" public variable to a string type and it works. Is
there a restriction on creating Public variables as Integer type?

My public declaration now reads:

Public userID As String

 

[Rick Brandt]

I changed the "userID" public variable to a string type and it works. Is there
a restriction on creating Public variables as Integer type?

Unless you declared you variable before as a Variant it could not possibly have
been Null. Variant is the only variable type that can contain a Null value. As
soon as you declare a variable as type Integer it will already have the value of
zero. If you even tried to set it to Null you would get an error.