JavaScript Function: Custom Error on the second number zero

JavaScript Error Handling: Exercise-3 with Solution

Throw Error for Division by Zero

Write a JavaScript function that accepts two numbers as parameters and throws a custom 'Error' if the second number is zero.

Sample Solution:

JavaScript Code:

// Define a function named divide_Numbers that takes two parameters: n1 and n2
function divide_Numbers(n1, n2) {
  // Check if n2 is equal to 0
  if (n2 === 0) {
    // If n2 is 0, throw an error indicating division by zero is not allowed
    throw new Error('Error: Division by zero is not allowed.');
  }  
  // If n2 is not 0, return the result of dividing n1 by n2
  return n1 / n2;
}
// Call the divide_Numbers function with arguments 8 and 3, then log the result to the console
console.log(divide_Numbers(8, 3));
// Call the divide_Numbers function with arguments 8 and 0, which will throw an error, and handle it
console.log(divide_Numbers(8, 0));

Output:

2.6666666666666665
"error"
"Error: Error: Division by zero is not allowed.

Note: Executed on JS Bin

Explanation:

In the above function "divide_Numbers()", we first check if n2 is equal to zero. If it is, we throw a custom Error with the message 'Error: Division by zero is not allowed.' This prevents the function from performing a division by zero operation, which would result in an error.

If n2 is not zero, the function continues and calculates the division of n1 by n2 using the division operator (/). The result is then returned.

Flowchart:

Live Demo:

See the Pen javascript-error-handling-exercise-3 by w3resource (@w3resource) on CodePen.

Improve this sample solution and post your code through Disqus.

Error Handling Exercises Previous: Handling TypeError with Try-Catch block.
Error Handling Exercises Next: Custom Error on a negative number.