The Latest

DevX - Software Development Resource

Inserting a Duplicate Record

Question: When creating a database (using the Access 1.1 engine) and selecting a field to be a primary index and requiring a unique index value, what will happen when the

DevX - Software Development Resource

Using Function Pointers/Dynamic Functions

Question: In Access 2.0 there is an Eval() function which will automatically evaluate numeric expressions. This functionality does not appear to exist in VB 4. I found an article in

DevX - Software Development Resource

ODBC Slowdown

Question: I am trying to create a “proof of concept” Visual Basic Project.In it, I am using a VB front end to access and maintain data in anORACLE 7 database

DevX - Software Development Resource

Wait Window

Question: My VB application accesses Oracle on VAX and it takes atleast15 secs to get connected to Oracle. How can I display a waitwindow/msgbox/form while it is trying to connect

DevX - Software Development Resource

Creating a Help File for an Excel Document

Question: I am trying to include a button in an Excel worksheet that will allow the user to click in to receive help infilling out the spreadsheet form properly. However,

DevX - Software Development Resource

Showing, Loading, and Unloading

Question: I have forms that I want to load, unload, and then load again. I use Show and Unload to do this. After I unload the form and try to

DevX - Software Development Resource

Using Large Dynasets

Question: I have a VB app that I use to correct records on an Rdb database on a VAX. I am using Microsoft’s TCP/IP and DEC’sODBC drivers. Our databases can

DevX - Software Development Resource

Using Help

Question: I cannot get the WinHelp API to work. “Bad DLL Convention” but I appear tobe doing everything right (including correction to WinAPI help declaration).Any suggestions? Answer: You could try

DevX - Software Development Resource

Maintaining Focus on a Command Button

Question: I see that an input box appears to maintain a focus on one the command buttons even when entering text. How is this done? Answer: What you are seeing

DevX - Software Development Resource

Using 3.0 Files in 4.0

Question: How do I upgrade my version 3.0 files to version 4.0? Answer: If you open your 3.0 project in any variant of VB 4.0, it will ask you if

DevX - Software Development Resource

Scrolling Image

Question: I cannot seem to find any documentation on how to scrollthe contents of a page. Can you help? Answer: The Visual Basic Knowlege Base, which is installed with Visual

DevX - Software Development Resource

Inserting Control Characters

Question: How do I insert carriage return (Chr(13)) and line feed (Chr (10)) in a text box at run-time? Answer: Just use the ampersand (&) and add them to the

DevX - Software Development Resource

Adding Fields to Existing Database

Question: How do I add new fields to an existing table in an Access 2.0 databasewithout losing data that already exists in the table/database? I knowhow to add fields, (the

DevX - Software Development Resource

Saving Data Before Exit

Question: If a user closes an application via the control box at the top LH side of a window, I would like to offer the user 3 choices:They can save

DevX - Software Development Resource

Using ToolTips

Question: How do I program the ToolTips (text that appears when the cursor is over a toolbar button) ? Answer: You should look into the Tips control from Mabry Software.

DevX - Software Development Resource

Putting More Controls on a Form

Question: If you are designing a program, but there is not enough room on a form even when it is maximized, what can you do? Answer: If you use a

DevX - Software Development Resource

Creating Long Delays

Question: I’ve been trying to create a simulator – it requires as close to real-time operation as possible. I have a couple of questions about timers.How do I activate a

DevX - Software Development Resource

Creating Huge Arrays with ReDim Keyword

Question: I am loading a file which is basically a list of numbers into an array. The array is declared as a string. I keep getting an “out of string

DevX - Software Development Resource

Source Control Tools

Question: We are developing a decent sized application in VB with a couple of programmers. We are looking for a way to have all of the programmers work on the

DevX - Software Development Resource

Selecting Visual Basic vs. Visual C++

Question: Where would you use Visual Basic over Visual C++? Answer: Well, personally, I’d almost always use VB over VC++ for a few reasons: Ease of use – it’s much

DevX - Software Development Resource

Embedding Double Quote Characters in Strings

Question: How can I include a double quote character in a string? I couldn’t find any masking characters like backslashin C. Answer: To include the double quote character within a

DevX - Software Development Resource

Global Variables Between Applications

Question: The VB4 help files state that Public Declarations in a General module are available to all forms andmodules in all applications. Is this true? I can’taccess such variables across

DevX - Software Development Resource

Installing Database Application

Question: I am having trouble using the setup wizard for a project I have created in Visual Basic. The problem is after I setup the program on another computer, the

DevX - Software Development Resource

Using the CancelError Property

Question: You said there’s an example in the VB help file on use of theCancelError = true property. Where is it? In my app, I can get VB to generatethe

DevX - Software Development Resource

Trapping Cancel Button

Question: In a simple loop on a form with a Cancel Button:DoHere I want to Check to see if a user pushed a cancel button(Cancel Property is set to true)(While

DevX - Software Development Resource

Closing a Database

Question: I have made a program to use a database, and will makea copy of this file to a disk. The problem is that Ican’t make a copy of the

DevX - Software Development Resource

Using Generic Objects

Question: I am using a subroutine which involves 2 list boxes in a pick box configuration. I take the literal boxname [Form.Control] and load it to a variable- BoxName. I

DevX - Software Development Resource

Saving Window Changes When Unloading

Question: How do you save the choices when changing forms and shutting down the program. Do I have to use a module to store the changes? Answer: If you have

DevX - Software Development Resource

Checking for Existence of a File

Question: How do you check to see if the name of a file you want to RENAME a file to already exists? Answer: Here is a great example of how

DevX - Software Development Resource

Using GROUP BY Clause

Question: I am writing a Lottery Simulator, I have a database which contains seven fields, each field of each record contains a number from 1 to 49. I am looking