PRB: SYS(2018) May Return More Than the Message Parameter

• Microsoft Visual FoxPro for Windows, versions 5.0, 5.0a, 6.0

SYMPTOMS

When a table is created programmatically, the Check clause can be used to perform field level validations. When a field level error occurs, either the SYS(2018) or the AERRORS function can be used to display the source of the error. In Visual FoxPro 3.0, the error message parameter that was involved in the generated error was returned. This behavior is different in Visual FoxPro 5.0 and 6.0. In the latter versions of Visual FoxPro, the entire error message is returned by default.

RESOLUTION

To work around this behavior use the Error cause in the CREATE TABLE, Check statement, as shown in the MORE INFORMATION section.

STATUS

This behavior is by design.

MORE INFORMATION

Steps to Reproduce Behavior

1. Run the following code to see the behavior. When the code executes, the program continues when an error occurs and the error is displayed using SYS(2018) and the AERRORs array. Run the code and first do not select the work around and you will see the default error message parameter. If you want to see the work around, the CREATE TABLE with the ERROR clause is used.

   Sample Code

   
         *-- Code begins here.
         CLEAR
         ON ERROR *
         IF ADIR(myTestFiles, "sys2018*.dbc") > 0
             nErase=MESSAGEBOX("Erase SYS(2018) Files?",4)
         ENDIF
         IF nErase = 6
             CLOSE DATA
             ERASE sys2018.*
             CREATE DATA sys2018
             OPEN DATA sys2018
             nError = MESSAGEBOX("Workaround?",4)
             IF nError = 6
                 CREATE TABLE sys2018 (NAME c(10) CHECK NAME="Moe" ;
                 ERROR "NAME")
             ELSE
                 CREATE TABLE sys2018 (NAME c(10) CHECK NAME="Moe")
             ENDIF
         ENDIF
   
         INSERT INTO sys2018 VALUES ("NotMoe")
   
         &&This causes a validation error.
         ?"SYS(2018) = " + SYS(2018)
         ?
         ?
         =AERROR(aTest)
         DISPLAY MEMO LIKE aTest
         CLOSE DATA ALL
         ON ERROR
      *-- Code ends here. 

   ERASE SYS2018.* 

REFERENCES

Visual FoxPro Help; search on: SYS(2018); AERROR

Additional query words: kbADO150 kbADO200 kbCtrl kbDatabase kbDataBinding kbvfp600 kbActiveX

Keywords :
Version : WINDOWS:5.0,5.0a,6.0
Platform : WINDOWS
Issue type : kbprb