Introduction to JavaScript – Control Flow
In this lesson, we’ll explore how we can use the building blocks of JavaScript to write programs that make decisions.
Control flow statements enable JavaScript programs to make decisions by executing code based on a condition. If a given condition is true, we execute one block of code. If the statement is false, we execute another block of code. For instance, if we were making a game in which the user had to choose which door to enter, we’d need a way for the program to know what to do once the user was in the next room.
Introduction to JavaScript – Control Flow
In this lesson, we’ll learn how to make decisions with JavaScript and how it can control the program’s flow.
let userName = 'Bernie'; //set your name in this variable.
let knowsJavaScript = false; //set this boolean to true or false and see results.
if (knowsJavaScript &&; userName) {
console.log('Great, ' + userName + '! Get ready to practice your JavaScript!');
} else if (knowsJavaScript) {
console.log('Great! Get ready to practice your JavaScript!');
} else if (userName) {
console.log('Great, ' + userName + '! Get ready to learn something new!');
} else {
console.log('Great! Get ready to learn something new!');
}
OUTPUT:
Great, Bernie! Get ready to learn something new!
Now follow this code: changed knowJavaScript = true
let userName = 'Bernie'; //set your name in this variable.
let knowsJavaScript = true; //set this boolean to true or false and see results.
if (knowsJavaScript && userName) {
console.log('Great, ' + userName + '! Get ready to practice your JavaScript!');
} else if (knowsJavaScript) {
console.log('Great! Get ready to practice your JavaScript!');
} else if (userName) {
console.log('Great, ' + userName + '! Get ready to learn something new!');
} else {
console.log('Great! Get ready to learn something new!');
}
OUTPUT:
Great, Bernie! Get ready to practice your JavaScript!
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