There are certain attention identifiers (AID) associates with every screen. Entry screens have ENTER and PF1 (Help) keys. Query screens have PF7 (Page Up), PF8 (Page down), PF1 (Help) and so on. Based on the key pressed by the user, the processing should happen in the program. EIBAID of DFHEIBLK has the last user pressed key. It can be verified in the program after the RECEIVE command.
The standard attention identifier list is DFHAID. It simplifies the testing of the contents of the EIBAID field after a Basic Mapping Support (BMS) or terminal control input operation.
The following content is present in the DFHAID copybook.
01 DFHAID. 02 DFHNULL PIC X VALUE IS ' '. 02 DFHENTER PIC X VALUE IS ''''. 02 DFHCLEAR PIC X VALUE IS '_'. 02 DFHCLRP PIC X VALUE IS '¦'. 02 DFHPEN PIC X VALUE IS '='. 02 DFHOPID PIC X VALUE IS 'W'. 02 DFHMSRE PIC X VALUE IS 'X'. 02 DFHSTRF PIC X VALUE IS 'h'. 02 DFHTRIG PIC X VALUE IS '"'. 02 DFHPA1 PIC X VALUE IS '%'. 02 DFHPA2 PIC X VALUE IS '>'. 02 DFHPA3 PIC X VALUE IS ','. 02 DFHPF1 PIC X VALUE IS '1'. 02 DFHPF2 PIC X VALUE IS '2'. 02 DFHPF3 PIC X VALUE IS '3'. 02 DFHPF4 PIC X VALUE IS '4'. 02 DFHPF5 PIC X VALUE IS '5'. 02 DFHPF6 PIC X VALUE IS '6'. 02 DFHPF7 PIC X VALUE IS '7'. 02 DFHPF8 PIC X VALUE IS '8'. 02 DFHPF9 PIC X VALUE IS '9'. 02 DFHPF10 PIC X VALUE IS ':'. 02 DFHPF11 PIC X VALUE IS '#'. 02 DFHPF12 PIC X VALUE IS '@'. 02 DFHPF13 PIC X VALUE IS 'A'. 02 DFHPF14 PIC X VALUE IS 'B'. 02 DFHPF15 PIC X VALUE IS 'C'. 02 DFHPF16 PIC X VALUE IS 'D'. 02 DFHPF17 PIC X VALUE IS 'E'. 02 DFHPF18 PIC X VALUE IS 'F'. 02 DFHPF19 PIC X VALUE IS 'G'. 02 DFHPF20 PIC X VALUE IS 'H'. 02 DFHPF21 PIC X VALUE IS 'I'. 02 DFHPF22 PIC X VALUE IS '¢'. 02 DFHPF23 PIC X VALUE IS '.'. 02 DFHPF24 PIC X VALUE IS '<'. |
For verification of values in EIBAID, Copy the standard AID list copybook provided by CICS in your program (COPY DFHAID). Now you can easily verify the key pressed as follows.
EVALUATE EIBAID
WHEN DFHENTER
PERFORM PARA-1
WHEN DFHPF1
PERFORM PARA-2
WHEN OTHER
PERFORM PARA-3
END-EVALUATE. |
The above checking is done in COBOL and this kind of check has to be done after every RECEIVE command to properly route the flow. CICS provides its own routing processing based on the key pressed by HANDLE AID command. This will be effective through out the program and reduce the code redundancy. The routing will be automatically invoked on every RECEIVE.
EXEC CICS HANDLE AID
DFHENTER(PARA-1)
DFHPF1(PARA-2)
ANYKEY(PARA-3)
END-EXEC. |
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