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Learning TypeScript 2.x - Second Edition
book

Learning TypeScript 2.x - Second Edition

by Remo H. Jansen
April 2018
Beginner content levelBeginner
536 pages
13h 21m
English
Packt Publishing
Content preview from Learning TypeScript 2.x - Second Edition

The double-selection structure (if...else)

The following code snippet declares a variable of type boolean and name isValid. Then, an if statement will check whether the value of isValid is equal to true. If the statement turns out to be true, the message Is valid! will be displayed on the screen. On the other hand, if the statement turns out to be false, the message Is NOT valid! will be displayed on the screen:

let isValid: boolean = true; 
 
if (isValid) { 
  console.log("Is valid!"); 
} else { 
  console.log("Is NOT valid!"); 
} 
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Publisher Resources

ISBN: 9781788391474Supplemental Content