Mandatory parameter field in selection screen

Question

Hi Experts,
As there are 2 options to get the input from the user. When I use select options because I need to make the field mandatory, it displays the output(blank) whenever there is no input/irrelevant input. When I use parameters, I cannot make it mandatory.
I need to display text boxes in the selection screen which should be mandatory and should only proceed when the user enters relevant data.
Please note that I have put the validation in the select options for a field like month as:
if s_month-low > '12' or s_month < '1'.
     MESSAGE 'Please enter a valid month' type 'E'.
endif.
but for a id, there is a search help. If the user do not enter the value from a search help, it displays the blank output. How to put validation on this?
Regards
Mani

Answer 1

Hi Mani,
You can do a validation at AT Selection Screen.Basically it will do a select single and try to fetch any line item.
A sample example as follows..
At Selection-Screen on S_DATE.
if S_date is not initial.
Perform validatedate.
Endif.
Form Validatedate.
Select single date
          from DB table
         where date in S_date.
endform.
if Sysubrc ne 0.
MESSAGE 'Please enter a valid month' type 'E'.
endif.
Regards,
Kannan