Tracing in Your Server Side AJAX Functions
You can add tracing to your AJAX functions by using the Framework VF_TRACENVALUE and VF_TRACEAVALUE built-in functions.
The information you trace appears in the trace window when you execute the Framework in trace mode. Here is an example of a AJAX function tracing a FETCH operation:
Subroutine Name(GET)
* Get the employee number supplied and trace it
Execute Subroutine(GETA) With_Parms(EMPNO ' ' 1 #EMPNO)
Use Builtin(VF_TraceAvalue) With_Args('GET received employee number' #EMPNO)
Fetch Fields(#PSLMST) From_File(PSLMST) With_Key(#EMPNO) Issue_Msg(*YES)
Execute Subroutine(PUTA) With_Parms(IO_STATUS ' ' 1 #IO$STS)
* If the record was found trace the salary and surname values retrieved
If_Status Is(*OKAY)
Use Builtin(VF_TraceNvalue) With_Args('GET request found salary' #Salary)
Use Builtin(VF_TraceAvalue) With_Args('GET request found surname' #Surname)
…etc…
VF_TRACEAVALUE and VF_TRACENVALUE
The VF_TRACEAVALUE and VF_TRACENVALUE Built-In functions are used to trace the logic flow and the values of variables in your browser command handlers and filters.
The values that are traced are added to the trace window that is displayed when Framework Web browser applications are executed in trace mode (by adding ?Trace=Y to the URL that Is used to start the application or by checking the Trace Mode On option).
Generally trace Built-In functions may be left in your code as they are only activated when trace mode is turned on. Do not do this in code sections that are executed many times per interaction.
For use with
|
LANSA for i |
YES |
|
Visual LANSA for Windows |
YES |
|
Visual LANSA for UNIX/Linux |
NO |
Arguments
| No | Type | Req/ Opt | Description | Min Len | Max Len | Min Dec | Max Dec |
|
1 |
A |
Req |
Event Description |
1 |
256 |
|
|
|
2 |
A N |
Opt |
Alphanumeric Value 1 to trace Numeric Value 1 to trace |
1 1 |
256 30 |
0 |
9 |
|
3 |
A N |
Opt |
Alphanumeric Value 2 to trace Numeric Value 2 to trace |
1 1 |
256 30 |
0 |
9 |
|
4 |
A N |
Opt |
Alphanumeric Value 3 to trace Numeric Value 3 to trace |
1 1 |
256 30 |
0 |
9 |
Return Values
None.
Technical Notes
The general usage rules apply to this Built-In function.
Examples
Example 1: This code fragment is seen in many applications generated by the Program Coding Assistant:
Use Builtin(VF_TRACEAVALUE) With_Args('#VF_EVENT value is unknown and has been ignored' #VF_EVENT)
Example 2: Trace some alpha values:
Use Builtin(VF_TRACEAVALUE) With_Args('Department and section are' #DEPTMENT #SECTION)
Example 3: Trace some numeric values:
Use Builtin(VF_TRACENVALUE) With_Args('Salary=' #SALARY)
Use Builtin(VF_TRACENVALUE) With_Args('Zip Code=' #POSTCODE)