1. Keyboard Input and Screen Display ––––––––––– Interactive Programming
Assignment 2
Keyboard Input and Screen Display
–––––––––––
Interactive Programming
IFS 210

2. Program Types Batch Interactive Input files Output files
No interaction with the users
Interactive
User types in data at the keyboard
Data is displayed on the screen
IFS 210

3. The Output Screen Used for low-volume output
Warning messages
Special conditions encountered in the data
Accomplished with the DISPLAY statement
DISPLAY {identifier / literal} …
DISPLAY PR-PATRON-NAME
DISPLAY “Sample Literal”
DISPLAY “Patron Name: ”, PR-PATRON-NAME
IFS 210

4. The DISPLAY Statement
Normally, after a DISPLAY statement is executed, the cursor will advance to the start of the next line.
The WITH NO ADVANCING phrase causes the cursor to remain where it is, following the last position of the display elements.
This is useful when your program queries the user and waits for a response.
IFS 210

5. The ACCEPT Statement
Allows the user to enter data from the keyboard into the program.
Example: ACCEPT WA-PAY-RATE
The program stops and waits for the user to enter data with keyboard and press <enter>.
The value typed by the user is stored in the variable WA-PAY-RATE
IFS 210

6. An Interactive Program (p. 115-)
Display an opening announcement
This described to the user the purpose of the program and provides an option to continue
Prompt the user for input data (two lines)
The name of the field
The picture of the field (string of X’s or 9’s)
Finally, the user is asked whether he wishes to enter another record.
IFS 210

7. Output Files
What happened to your EARNINGS.RPT file when you ran the program (Assignment 1) a second time?
Was the new report appended to the end of the file, or was the file re-written?
IFS 210

8. Pseudocode (EMPADD) 000-create-patron-file.
1. PERFORM 100-display-announce-screen
2. OPEN patron file (extend mode)
3. PERFORM UNTIL do-not-continue
a. PERFORM 200-accept-patron-record
b. WRITE patron record
c. Query user about continuing
4.Close patron file
5.Stop run
100-display-announce-screen.
1. DISPLAY description of program
2. Query user about continuing
200-accept-patron-record.
1. DISPLAY and ACCEPT the fields
IFS 210