9.12. Swift if…else statement

One if statement can be followed by an optional else statement else statement in a Boolean expression false when it is executed.

9.12.1. Grammar #

In Swift language if...else syntax of the statement:

if boolean_expression {
   /* The statement to be executed if the Boolean expression is true */
} else {
   /* The statement to be executed if the Boolean expression is false */
}

If the Boolean expression is true , then execute if the code within the block. If the Boolean expression is false , then execute else the code within the block.

9.12.2. Flow chart #

9.12.3. Example #

import Cocoa

var varA:Int = 100;

/* Detect Boolean conditions */
if varA < 20 {
   /* If the condition is true, execute the following statement */
   print("varA ＜ 20");
} else {
   /* If the condition is false, execute the following statement*/
   print("varA ＞ 20");
}
print("The value of the varA variable is \(varA)");

When the above code is compiled and executed, it produces the following results:

varA ＞ 20
The value of the varA variable is 100