Conditional Statement in COBOL

Introduction

  • The result of conditional statements are always true or false.
  • These statements change the flow of execution depending on the certain conditions defined by the programmer.

Types of conditional statements

Following are the various types of conditional statements:
1) IF condition statement
2) Relation condition
3) Sign condition
4) Class condition
5) Condition-name condition
6) Navigate condition
7) Combined condition

IF condition statement

  • This statement checks the condition. If the condition is true, then IF block is executed. If the condition is false, then the ELSE block is executed.
  • To end the IF block END-IF is used. Instead of END-IF a period can be used.
  • The use of END-IF is always preferable for the multiple IF blocks.
  • If the IF block is occurring inside another IF block, then it is known as nested IF.
Syntax:
IF [condition] THEN
    [COBOL statements]
ELSE
    [COBOL statements]
END-IF

Example : Program to demonstrate IF condition statement

IDENTIFICATION DIVISION.
PROGRAM-ID. ICS.

DATA DIVISION.
   WORKING-STORAGE SECTION.
   01 N1 PIC 9(3).
   01 N2 PIC 9(3).
   01 N3 PIC 9(4).
   01 N4 PIC 9(4).

PROCEDURE DIVISION.
   A000-FIRST-PARA.
   MOVE 30 TO N1 N3.
   MOVE 12 TO N2 N4.
   
   IF N1 > N2 THEN
      DISPLAY 'IF BLOCK OF LOOP 1'
      
      IF N3 = N4 THEN
         DISPLAY 'IF BLOCK OF IN LOOP 2'
      ELSE
         DISPLAY 'ELSE BLOCK OF IN LOOP 2'
      END-IF
      
   ELSE
      DISPLAY 'ELSE BLOCK OF IN LOOP 1'
   END-IF.
   
STOP RUN.


Output:
IF BLOCK OF LOOP 1
ELSE BLOCK OF IN LOOP 2