JavaScript Control Flow

Control flow statements let you change that order, based on conditions, loops or keywords.

Default Flow

Default flow executes code sequentially

(from top to bottom / from left to right).

Example

Flow sequentially:

let x → let y → let z.
let x = 5;
let y = 6;
let z = x + y;

Conditional Control Flow

if if...else switch ternary (? :)

Example

Flow branches depending on conditions:

let text = "Unknown";
if (age >= 18) {
text = "Adult";
} else {
text = "Minor";
}
Loops (Repetition Control Flow)

Example

Repeat flow until a condition (i < 5) is false.

for (let i = 0; i < 5; i++) {
text += "The number is " + i + "<br>";
}

Jump Statements

break - exits a loop or switch continue - skips the current loop iteration return - exits from a function throw - jumps to error handling

Example

for (let i = 0; i < 10; i++) {
if (i === 3) { break; }
text += "The number is " + i + "<br>";
}

Function Flow

Functions are callable and reusable code blocks

Example

function myFunction(p1, p2) {
return p1 * p2;
}

JavaScript Is Single-Threaded