PRB: Accessing Visual FoxPro 3.0 Files from Visual Basic 4.0

• Standard, Professional, and Enterprise Editions of Microsoft Visual Basic, 32-bit only, for Windows, version 4.0
• Microsoft FoxPro for Windows, version 3.0

SYMPTOMS

When you attempt to open a Microsoft FoxPro for Windows database file by connecting the database file to a Data Control in a Visual Basic version 4.0 program, the DatabaseName dialog box selects only files with the .dbf file name extension. Moreover, if you select a file with the .dbc file name extension, the DatabaseName property of the Data control displays the path without the file name.

CAUSE

This behavior occurs because the Data control in Visual Basic assumes that a .dbc file is an unlinked FoxPro 3.0 table.

The 16-bit edition of Visual Basic version 4.0 cannot read files in the Visual FoxPro version 3.0 format.

RESOLUTION

Use the following steps to work around this problem:

1. Set the Connect property of the Data1 Data control to FoxPro DBC.

2. Add the FoxPro 3.0 database file name to the path in DatabaseName property of the Data control. This file must have the .dbc file name extension.

3. Select a table in the RecordSource property of the Data control. You can now use bound controls on this recordset.

STATUS

Microsoft has confirmed this to be a problem in Visual Basic version 4.0 for Windows. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

FoxPro 3.0 Databases and their associated linked tables are read-only in the 32-bit edition of Visual Basic version 4.0. The 16-bit edition of Visual Basic version 4.0 can read files in the Visual FoxPro version 3.0 format with the .dbc or .dbf file name extension. FoxPro creates three types of files that Visual Basic can open through Data Access Methods.

• Databases: Has the file name extension .dbc.
• Linked Tables: Has the file name extension .dbf.
• Unlinked Table: Also has the file name extension .dbf.

If you get the error, "Cannot Access the Bound FoxPro 3.0 bound DBF file," the Data control is attempting to access a linked table as a stand alone table. Follow the steps shown in the Workaround section to eliminate this error message.

Steps to Reproduce Problem

1. Start the 32-bit version of Visual Basic 4.0, or if it is already running, click New Project on the File menu.

2. From the toolbox, add a Data control button to the Form1 form.

3. Click the Connect property of the Data Control and then click the down arrow to select FoxPro 3.0.

4. Click the DatabaseName property of the Data Control and then click the ellipses button to display the DatabaseName dialog box. Note the default file name extension is .dbf.

5. Select a .dbc file and click the OK button. Note that Visual Basic has truncated the file name out of the database name text box.