[RBASE-L] - Re: How to tell if VARBIT column IS NULL

[Dennis McGrath]

Cool stuff. When does it get into the online GETPROPERTY Page?

-----Original Message-----
From: rbase-l@rbase.com [mailto:rbas...@rbase.com] On Behalf Of A. Razzak Memon
Sent: Thursday, February 12, 2009 2:06 PM
To: RBASE-L Mailing List
Subject: [RBASE-L] - Re: How to tell if VARBIT column IS NULL

At 10:23 AM 2/12/2009, Lawrence Lustig wrote:

>I have a VARBIT column containing images. In my form, I want
>to determine whether the column is NULL or contains an image
>and adjust my user interface accordingly.


Did you know that you can use the eXtended option of GETPROPERTY
command, related to Table_Column, to achieve your goal?

Syntax:

GETPROPERTY TABLE_COLUMN[TableName->ColumnName] ISNULL varname

Resulting "varname" will return to value of "TRUE" or "FALSE"

. TRUE if NULL
. FALSE if NOT NULL


Here's how:

01. Start R:BASE 7.6 (Build: 7.6.6.30214), or R:BASE Turbo V-8
     (Build: 8.0.20.30214), or R:BASE eXtreme 9.0 (64), or
     R:BASE eXtreme 9.0 (32) Build: 9.0.1.10214.

02. CONNect to appropriate database and open the desired form
     in Form Designer.

     OR

     CONNect to RRBYW15
     Form Name: Contacts
     Table Name: Contact

03. While in Form Designer, use the following GETPROPERTY
     command as "Table | On Row Entry" Custom EEP.

     Form Designer | Main Menu | Tables | Add/Remove Tables...

     Table Settings | Entry/Exit Procedures | On Row Entry:

     Custom EEP:
     -- Based on Table: Contact, Column: ContPhoto (VARBIT)

     GETPROPERTY TABLE_COLUMN[Contact->ContPhoto] ISNULL vValue
     RECALC VARIABLES
     RETURN

04. Now based on the resulting variable "vValue", do what you
     need to do to change the user interface accordingly.

That's all there is to it.

Very Best R:egards,

Razzak.