How To Modify a Rule's Table to Which It Belongs in VFP 5.0

• Microsoft Visual FoxPro for Windows, version 5.0

SUMMARY

In Visual FoxPro 5.0, the field validation rules and the record validation rules can now modify the table to which they belong. This is not possible in Visual FoxPro 3.0.

MORE INFORMATION

For example, suppose you want to track when each update was made to a record, check a maximum order amount, and capitalize entries in a certain field. The following steps illustrate how this might be done.

1. Create a new DBC called "mydbc."

2. Issue the following command to create a table:

         CREATE TABLE cust(custname c(10),chg_date D, order N(5), ;
         max N(5), limit L)
   

3. Enter some records in the table.

4. Modify the table, and in the record validation rule type rec_valid().

5. In the field validation rule for custname type fld_valid().

6. Enter the following in the stored procedures:

         PROCEDURE rec_valid
            REPLACE chg_date WITH DATE()
            IF order > max
               REPLACE limit With .t.
            ELSE
               REPLACE limit with .f.
            ENDIF
         ENDPROCEDURE
   
         PROCEDURE fld_valid
           IF !EMPTY(ALLTRIM(custname)) AND ;
              ALLTRIM(PROPER(custname))<>ALLTRIM(custname)
               REPLACE custname WITH PROPER(custname)
           ENDIF
         ENDPROCEDURE
   
   

7. Browse the table, add new records, and edit existing records.