PRB: CLEAR ALL Removes Back-Links from Data Environment Object

MORE INFORMATION

Data Environments can be classed programatically. Once instantiated, you may issue the CLEAR ALL command with open tables and database containers. If the CLEAR ALL command is issued with an open Data Environment Object, the tables open at that time lose their links to the database container.

This does not occur with forms' Data Environments.

Code to Demonstrate Behavior

The following program demonstrates this behavior. Each time this program is run subsequent to the first time, Visual FoxPro produces the error listed above for each table that the DataEnvironment class defines.

SET DEFAULT TO c:\vfp
CLOSE DATA
oDe = CreateObject('de')
CLEAR ALL    && remove this line, and run the program twice to
             && resolve the problem

DEFINE CLASS de AS DataEnvironment

Name = "DE"
AutoCloseTables = .F.
AutoOpenTables = .T.
InitialSelectedAlias = "customer"

ADD OBJECT oCustomer AS cursor WITH ;
   Alias = 'customer', ;
   Database = CURDIR() + 'samples\data\testdata.dbc', ;
   CursorSource = 'customer', ;
   Exclusive = .T.

PROCEDURE Init
   THIS.OpenTables
ENDPROC
ENDDEFINE