JavaScript else
The else Statement
Use the else statement to specify a block of code to be
executed if a condition is false.
if (condition) {
// block of code to be executed if the condition is true
} else {
// block of code to be executed if the condition is false
}
// block of code to be executed if the condition is true
} else {
// block of code to be executed if the condition is false
}
Example
If the hour is less than 18, create a "Good day" greeting, otherwise "Good evening":
if (hour < 18) {
greeting = "Good day";
} else {
greeting = "Good evening";
}
Try it Yourself »
greeting = "Good day";
} else {
greeting = "Good evening";
}
The else if Statement
Use the else if statement to specify a new condition
if the first is false.
Syntax
if (condition1) {
// block of code to be executed if condition1 is true
} else if (condition2) {
// block of code to be executed if the condition1 is false and condition2 is true
} else {
// block of code to be executed if the condition1 is false and condition2 is false
}
// block of code to be executed if condition1 is true
} else if (condition2) {
// block of code to be executed if the condition1 is false and condition2 is true
} else {
// block of code to be executed if the condition1 is false and condition2 is false
}
Example
If time is less than 10:00, create a "Good morning" greeting, if not, but time is less than 20:00, create a "Good day" greeting, otherwise a "Good evening":
if (time < 10) {
greeting = "Good morning";
} else if (time < 20) {
greeting = "Good day";
} else {
greeting = "Good evening";
}
Try it Yourself »
greeting = "Good morning";
} else if (time < 20) {
greeting = "Good day";
} else {
greeting = "Good evening";
}
Example
This example will write a link to either W3Schools or to the World Wildlife Foundation (WWF). By using a random number, there is a 50% chance for each of the links.
let text;
if (Math.random() < 0.5) {
text = "<a href='https://w3schools.com'>Visit W3Schools</a>";
} else {
text = "<a href='https://wwf.org'>Visit WWF</a>";
}
document.getElementById("demo").innerHTML = text;
Try it Yourself »
if (Math.random() < 0.5) {
text = "<a href='https://w3schools.com'>Visit W3Schools</a>";
} else {
text = "<a href='https://wwf.org'>Visit WWF</a>";
}
document.getElementById("demo").innerHTML = text;