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JavaScript if


The JavaScript if Statement

Use the JavaScript if statement to execute a block of code when a condition is true.

Syntax

if (condition) {
  //  block of code to be executed if the condition is true
}

Note that if is in lowercase letters. Uppercase letters (If or IF) will generate a JavaScript error.

Example

Make a "Good day" greeting if the hour is less than 18:00:

if (hour < 18) {
  greeting = "Good day";
}

The result of greeting will be:

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Examples

let age = 18;
let text = "You can Not drive";

if (age >= 18) {
  text = "You can drive");
}
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let age = 16;
let text = "You can Not drive";

if (age >= 18) {
  text = "You can drive");
}
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Nested if

You can use an if statement inside another if statement:

Example

let age = 16;
let country = "USA";
let text = "You can Not drive!";

if (country == "USA") {
  if (age >= 16) {
    text = "You can drive!";
  }
}
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Nested if statements can make your code more complex.

A better solution is to use the logical AND operator:

Example

let age = 16;
let country = "USA";
let text = "You can Not drive!";

if (country == "USA" && age >= 16) {
  text = "You can drive!";
}
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