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Introduction to JavaScript
course content

Course Content

Introduction to JavaScript

Introduction to JavaScript

1. JavaScript Fundamentals
About JavaScriptUnderstanding JavaScript SyntaxChallenge: Console Output in JavaScriptUsing Comments to Document CodeChallenge: Write a Single-Line CommentChallenge: Write a Multi-Line Comment
2. Variables and Data Types in JavaScript
Understanding Variables in JavaScriptChallenge: Define the VariableUsing const for ConstantsExploring JavaScript Data TypesWorking with null in JavaScriptIntroduction to ArraysArray Methods and ManipulationChallenge: Perform Array Operations
3. Performing Operations in JavaScript
Understanding Assignment OperatorsMathematical Operations in JavaScriptAssignment Operators in JavaScriptIncrement and Decrement OperatorsChallenge: Variable Operations PracticeComparison Operators in JavaScriptLogical Operators ExplainedChallenge: Compare Variables in JavaScriptConcatenating Strings in JavaScriptChallenge: Build Sentences with JavaScript
4. Controlling Program Flow with Conditional Statements
Mastering if Statements in JavaScriptUsing else for Alternative OutcomesApplying else if for Multiple ConditionsChallenge: Determine Sizes with Conditionals
5. Looping Through Data in JavaScript
Understanding the while Loop in JavaScriptUsing the do while Loop for IterationChallenge: Print Numbers from 5 to 9Mastering the for Loop in JavaScriptChallenge: Console Tigers with LoopsBreaking Out of Loops with breakSkipping Iterations with continueChallenge: Stop and Skip in Loops
6. Functions in JavaScript
What Are Functions in JavaScript?Defining Functions in JavaScriptChallenge: Write a Function – My NameUsing Function Arguments EffectivelyReturning Values from FunctionsChallenge: Create a Sum FunctionCourse Summary & Next Steps

book
Using the do while Loop for Iteration

Let's consider the do-while loop. This loop is similar to the while loop but has a key distinction.

whiledo-while
Executes code block after the condition check.Executes code block before the condition check.

Syntax

The do-while loop begins with the do keyword, encloses the code block within curly braces {}, and concludes with the while keyword followed by the condition in parentheses () without the need for an additional code block:

Here's an example:


              
123456

            
let a = 0;

do {
  console.log(a);
  a++;
} while (a <= 3 && a >= 1);
copy

At the outset, the variable a was initialized to 0, and the condition a >= 1 was evaluated after the a++ operation.

The code block within the do is guaranteed to be executed at least once:


              
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// `while` loop
while (false) {
  console.log("while"); // Not executed
}

// `do-while` loop
do {
  console.log("do-while"); // Executed 1 time
} while (false);
copy

The do-while loop is particularly useful when you need to prompt the user for input at least once and continue until the user enters valid data or meets a specific condition.

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Section 5. Chapter 2
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