Definition:
It is a part of error handling that sends an error to the catch block, and the main difference is that it uses a custom error created by the programmer
based on their requirements.
You can use it with try-catch error handling method.
When the program runs, JavaScript executes the code line by line until it reaches the throw statement.
When the program reaches a throw statement, it immediately stops execution and shows the custom error.
So, a throw error is a custom error that you can create yourself whenever you want.
Now you can clearly understand how throw error works with the help of this flowchart.
Start | v Write your code in a Try block | v Run Try block | v Is there any error? / \ Yes No | | v v Run Catch Try block block finishes | | v v Show "error" End | v End
Syntax:
throw "Error message";Example:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Throw Error Example</title>
</head>
<body>
<h1>JavaScript Throw Error Example</h1>
<p>Open the console (F12) to see the output.</p>
<script>
// Throw Error Example
try {
let age = 15; // This is wrong age
if (age < 18) {
throw new Error("Age must be 18 or above!");
}
console.log("Access Granted!");
}
catch (error) {
console.log("Error: " + error.message);
}
</script>
</body>
</html>
Output:
Error: You must be 18 or above!