JavaScript Conditional Statements Explained
Conditional statements in JavaScript are used to make decisions based on conditions. They help execute different blocks of code depending on whether a condition is true or false.
1. if Statement
Runs the code only if the condition is true.
Example:
let age = 20;
if (age >= 18) {
console.log("You are eligible to vote.");
}
Output
You are eligible to vote.
2. if...else Statement
Executes one block if true, another if false.
Example:
let isRaining = false;
if (isRaining) {
console.log("Take an umbrella.");
} else {
console.log("No need for an umbrella.");
}
Output
No need for an umbrella.
3. if...else if...else Statement
Checks multiple conditions in order.
Example:
let score = 75;
if (score >= 90) {
console.log("Grade: A");
} else if (score >= 70) {
console.log("Grade: B");
} else {
console.log("Grade: C or below");
}
Output
Grade: B
4. switch Statement
Used to test multiple values against a single variable.
Example:
let day = 3;
switch (day) {
case 1:
console.log("Monday");
break;
case 2:
console.log("Tuesday");
break;
case 3:
console.log("Wednesday");
break;
default:
console.log("Another day");
}
Output
Wednesday