Proper way to use error handling in Javascript

Tosh
2 min readApr 18, 2021

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In programming unintended side-effects called errors can and will happen in your code. Allowing these errors to be introduced to people that are using your programs is frowned upon and a very bad user experience.

Error Handling is the technique of smoothly handling these errors and providing useful information to a user.

Here are the important parts of error handling:Try

The try block allows you to try an initial blog of code.

async function doWork() {  try {
let response = await fetch("www.worktobedone.com")
let work = await response.json() return work
}
}

To use Catch

To use the catch block allows you to catch an error from the initial blog of code.

async function doWork() {  try {
let response = await fetch("www.worktobedone.com")
let work = await response.json() return work
} catch(error) {
// Here we caught an error to alert
alert(error)
}
}

Use Throw

To use the throw keyword allows you to control or create custom exceptions from your code.

async function doWork() {  try {
let response = await fetch("www.worktobedone.com")
let work = await response.json() return work
} catch(error) {
// Lets change the error output
throw new Error(`Oops we found this error during work - ${error}`)
}
}

Conclusion

So finally block allows you to execute code regardless of errors in the try and catch blocks.

async function doWork() {  try {
let response = await fetch("www.worktobedone.com")
let work = await response.json() return work
} catch(error) {
throw new Error(`Oops we found this error during work - ${error}`)
} finally {
return "My work here is done."
}
}

More error handling

This step by step tutorial showed the steps to using the try..catch…finally block to handle errors. If you enjoyed this post feel free to leave a comment about your thoughts and experiences handling errors in your code.

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Tosh
Tosh

Written by Tosh

Software Engineering student @Flatiron

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