Hello, I'm Duke
In the previous 2 sessions, I have guided you on how to develop, compile and create a simple calculation program using COBOL.
Now, I will systematize the knowledge of the previous two articles and explain more about COBOL syntax
1. Variable declaration
Data in COBOL is declared in the DATA DIVISION
and variables are usually defined in the WORKING-STORAGE SECTION.
IDENTIFICATION DIVISION.
PROGRAM-ID. SimpleVariable.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 WS-NAME PIC A(20) VALUE 'Duke'.
01 WS-AGE PIC 9(2) VALUE 32.
PROCEDURE DIVISION.
Main-Process.
DISPLAY 'Name: ' WS-NAME.
DISPLAY 'Age: ' WS-AGE.
STOP RUN.
-
WS-NAME
is a string variable of length 20 and default value is 'Duke'. -
WS-AGE
is a 2-digit integer variable with default value 32. - The program displays the declared name and age
2. Condition (IF..ELSE) statement
COBOL allows the use of IF
... ELSE
statements to test conditions and control the flow of execution based on the test results.
IDENTIFICATION DIVISION.
PROGRAM-ID. LoginCheck.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 WS-USERNAME PIC X(20).
01 WS-PASSWORD PIC X(20).
01 WS-STORED-USERNAME PIC X(20) VALUE 'Duke'.
01 WS-STORED-PASSWORD PIC X(20) VALUE 'HjhXhxw8-P]wY4;'.
PROCEDURE DIVISION.
Main-Process.
DISPLAY 'Enter your username: '.
ACCEPT WS-USERNAME.
DISPLAY 'Enter your password: '.
ACCEPT WS-PASSWORD.
IF WS-USERNAME = WS-STORED-USERNAME AND
WS-PASSWORD = WS-STORED-PASSWORD
DISPLAY 'Login successful! Welcome, ' WS-USERNAME '!'
ELSE
DISPLAY 'Invalid username or password!'.
STOP RUN.
and here is the result
Repository here