7 99 2 VALUECHECK Examples

LANSA Technical

7.99.2 VALUECHECK Examples

Structuring Functions for Inline Validation

Structuring Functions to Use a Validation Subroutine

Using the VALUECHECK Command for Inline Validation

Using the VALUECHECK Command for Validation with a Subroutine

Structuring Functions for Inline Validation

Typically, functions using validation commands (e.g.: CONDCHECK, DATECHECK, FILECHECK, RANGECHECK and VALUECHECK) are structured for inline validation like this:

BEGIN_LOOP 
REQUEST   << INPUT >>
BEGINCHECK 
         << USE CHECK COMMANDS TO VALIDATE INPUT HERE >>
ENDCHECK  
         << PROCESS THE VALIDATED INPUT HERE >>
END_LOOP  
 

If a validation command inside the BEGINCHECK / ENDCHECK command block detects a validation error control is passed back to the REQUEST command. This happens because of the default IF_ERROR(*LASTDIS) parameter on the ENDCHECK command.  

Structuring Functions to Use a Validation Subroutine

Typically functions using validation commands (e.g.: CONDCHECK, DATECHECK, FILECHECK, RANGECHECK and VALUECHECK) are structured for subroutine validation like this:

DEFINE    FIELD(#ERRORCNT) REFFLD(#STD_NUM)
DEF_COND  NAME(*NOERRORS) COND('#ERRORCNT = 0')
         
BEGIN_LOOP 
DOUNTIL   COND(*NOERRORS)
REQUEST   << INPUT >>
EXECUTE   SUBROUTINE(VALIDATE)
ENDUNTIL  
         << PROCESS THE VALIDATED INPUT HERE >>
END_LOOP  
         
SUBROUTINE NAME(VALIDATE)
CHANGE    FIELD(#ERRORCNT) TO(0)
BEGINCHECK KEEP_COUNT(#ERRORCNT)
         << USE CHECK COMMANDS TO VALIDATE INPUT HERE >>
ENDCHECK  IF_ERROR(*NEXT)
ENDROUTINE 
 

If a validation command inside the BEGINCHECK / ENDCHECK command block detects a validation error control is returned to the main function loop with #ERRORCNT > 0. 

Using the VALUECHECK Command for Inline Validation

This example demonstrates how to use the VALUECHECK command within the main program block to check that a department code is one of a set of values.

DEF_LIST  NAME(#EMPBROWSE) FIELDS(#EMPNO #DEPTMENT)
         
BEGIN_LOOP 
REQUEST   FIELDS(#EMPNO #DEPTMENT) BROWSELIST(#EMPBROWSE)
         
BEGINCHECK 
VALUECHECK FIELD(#DEPTMENT) WITH_LIST(ADM AUD FLT GAC) MSGTXT('The department code entered is not valid')
ENDCHECK  
         
ADD_ENTRY TO_LIST(#EMPBROWSE)
END_LOOP  
 

If the value of #DEPTMENT is not in the list of values specified with the 'WITH_LIST' parameter the message defined in the VALUECHECK command is issued and program control returns to the last screen displayed. In this case the last screen displayed is the REQUEST screen.

Using the VALUECHECK Command for Validation with a Subroutine

This example demonstrates how to use the VALUECHECK command inside a subroutine to check a department code is in a set of values.

After the user enters the requested details the VALIDATE subroutine is called. It checks that the value of #DEPTMENT is in the set of values specified with the 'WITH_LIST' parameter. If it is not the message defined in the VALUECHECK command is given and the DOUNTIL loop executes again. When a value for # DEPTMENT is entered that is in the set of specified values the DOUNTIL loop ends and processing of the verified input is done.

DEFINE    FIELD(#ERRORCNT) TYPE(*DEC) LENGTH(3) DECIMALS(0) DEFAULT(0)
DEF_COND  NAME(*NOERRORS) COND('#ERRORCNT = 0')
DEF_LIST  NAME(#EMPBROWSE) FIELDS(#EMPNO #DEPTMENT)
         
BEGIN_LOOP 
DOUNTIL   COND(*NOERRORS)
REQUEST   FIELDS(#EMPNO #DEPTMENT) BROWSELIST(#EMPBROWSE)
EXECUTE   SUBROUTINE(VALIDATE)
ENDUNTIL  
ADD_ENTRY TO_LIST(#EMPBROWSE)
END_LOOP  
         
SUBROUTINE NAME(VALIDATE)
CHANGE    FIELD(#ERRORCNT) TO(0)
         
BEGINCHECK KEEP_COUNT(#ERRORCNT)
VALUECHECK FIELD(#DEPTMENT) WITH_LIST(ADM AUD FLT GAC) MSGTXT('The department code entered is not valid') 
ENDCHECK  IF_ERROR(*NEXT)
         
ENDROUTINE