Conversion considerations

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A few things to note when the converter has finished:

This converter was designed to create dBASE Plus compatible objects from your screen and menu layouts. In doing so, our priority was to insure the layouts were converted correctly. Still, your form or menu’s design will most likely require some modification (changing the widths of some objects, possibly moving some objects a small amount).

Some of your source code may not have been converted correctly. Lacking a huge language translation utility, it simply isn't possible to insure the correct conversion of all source code. Use the Source Editor to correct any conversion errors.

The converter creates forms that use the OODML (Object Oriented Database Manipulation Language) of dBASE Plus, which is not necessarily going to be familiar to you. When tables are opened, they are opened using Query objects, rather than the USE command, and datalinks to fields in the tables refer to the appropriate Field objects. To become acquainted with OODML:

Read through other parts of this User’s Guide

Check the dBASE Knowledgebase at www.dBase.com

Subscribe to, and participate in, a few of the many dBASE newsgroups at news://news.dBase.com. They're free!

When the converter runs, it reads all the form and menu definitions in the .DFM, .MNU and .PRG files, and creates individual files for each one. This means you end up with more files than you started with. For example, if you have a .DFM with two form definitions, you’ll end up with two .WFM (Windows Form) files. The resulting filenames may look a bit strange, but this is only because the converter combines the names of the object and source files: The ACCT_REC.DFM file from the dBASE 5.0 for DOS CUA Samples folder is converted to ACCT_REC_ACCT_REC.WFM.

When the converter creates a menu file, it checks to see if there is a form's menuFile property set to point to it, and if so, attempts to set that property in the new .WFM file. Therefore, the menus should be correctly associated with the forms.

Properties of a form that were defined programmatically, using expressions or variables, will be converted to their default values. For example, a .DFM may have defined the top property based on a value relative to another form. In this case, the top property is likely to be set to zero when the .WFM is created by the converter. This is necessary because there is no good way for the converter to know the relative value these values refer to.

Procedures in your forms and menus may be converted to the .wfm or .mnu file with the code itself placed inside of a "comment block". This is a block of text that appears between the comment block symbols /* and */. For example:

  procedure PUSHBUTTON1_ONCLICK

   / *

   select acct_rec

   */

The code is present and hooked up to the pushbutton, but will not execute until you have a chance to make sure it’s correct. If the procedure involves data manipulation, it will most likely fail and you’ll need to replace it with OODML syntax. If the code looks correct, you can remove the comment blocks, keeping in mind that tables are not opened with the old dBASE for DOS syntax. They are opened in the new dBASE Plus (dBL) syntax, using Query objects. The converter wizard will attempt to put referenced procedures, from a procedure file, into the form or menu.

If you have any "#INCLUDE" statements, make sure you copy the include files to the new source location.

If your programs, or forms, require the use of .BIN or other external binary files, chances are they will not work in dBASE Plus. You’ll need to come up with a dBL way to perform their function, or find another solution (i.e., ActiveX, or other third-party tools).

Some menu keystrokes do not work in Windows (Ctrl-Ins, for example). Opening these menus in the Designer may result in errors pointing to these statements. The simplest way to deal with this would be to comment that line of code out (or delete it) by placing a * or // in front of the line of code. Open the menu in the Designer, and in the error dialog, click "Fix" and place the * or // characters in front of the line of code.

If your form produces the error message, "Unallowed phrase or keyword: .oBForm", click the "Fix" button and place either a * or // in front of the statement;

   RELEASE _CmdWindow.oBForm

to comment this line out. Then Save and Exit (Ctrl+W) the editor.

Remember, the converter is here to help bring the screen and/or menu layouts into dBASE Plus. Expect to do some modification to the results.

An Option

• Copy just the screen and/or menu code from files that involve the layout. Do not copy any actual code that manipulates the data. Basically, copy the screen design code, the "constructor code", to a new .DFM, and save it in a new folder.

• Run the converter to bring over the definitions of your screens and menus.

• Run dQuery to create a datamodule.

• Open the new dBASE Plus form in the form designer.

• Place the dataModule object on the form surface, and change all the datalinks to the dataModule (if you have multiple tables, make sure you get the right ones).

• Delete the query objects that are on the form.

In the dataModule, you can place a lot of your validation, and other, code, create links between tables, and so on. This places everything in the one, re-usable, file.