JavaScript Error Handling

In this tutorials we will see how to hanle error in JavaScript. Error handling is an important part of JavaScript Application when we write code. JavaScript provides several ways to handle errors such as try-catch blocks, throw statements and error objects.

There are a number of reasons that may cause errors. Here are some of the main error handling techniques in JavaScript.

1. Try-Catch Blocks
2. Throw Statements
3. Error Objects

1. Try-Catch Blocks

try-catch blocks allow you to catch and handle errors in your code. The try block contains the code that may throw an error, while the catch block contains the code that handles the error.

Example

try {
  // Code that may throw an error
  throw new Error("Something went wrong");
} catch (error) {
  // Code that handles the error
  console.error(error);
}

2. Throw Statements

throw statements allow you to throw custom errors in your code. You can throw any object that inherits from the Error object, such as a SyntaxError or a TypeError.

Example

function divide(a, b) {
  if (b === 0) {
    throw new Error("Cannot divide by zero");
  }
  return a / b;
}

3. Error Objects or Types

JavaScript provides several built-in error objects, such as SyntaxError, TypeError, and ReferenceError. These objects contain information about the type of error, the line number, and the stack trace. You can use these objects to catch specific types of errors and provide more detailed error messages to the user.

Example

try {
  // Code that may throw a TypeError
  let x = null;
  x.someMethod();
} catch (error) {
  if (error instanceof TypeError) {
    console.error("TypeError: " + error.message);
  } else {
    console.error(error);
  }
}

By using these error handling techniques, you can write more reliable and robust JavaScript code that can handle unexpected conditions and provide a better user experience.

---

Prev Next