Swift Error Handling - Do, Try, Catch - iOS Interview Question Series

The next topic in my series on iOS Interview questions explains error handling and the do, try, catch syntax in iOS and Swift. This iOS interview question was asked in a few interviews, so it's a good topic to learn. In this tutorial I walk though some basic error handling on a log in screen using the Do, Try, Catch syntax in Swift.

This is part of a series of videos about iOS interview questions in Swift. Check out the overview where I list and briefly discuss all the topics that are in this series:

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#swift #softwaredeveloper #iosdeveloper

[renagurbanovasenglish]

Thank you, even after 6 years, your code and teaching is still actual

[bigmtnstudio]

Awesome video! I like how you reinforced the "throw" keyword in there. 😃 The repetition makes it stick! Thanks, Sean.

[slasht]

If I have to learn any difficult concept, I look up your videos. You explain it better than anybody else.

[javierv.]

Dude every question I have about iOs, you have a video on it... thx A LOT!!! Happy new years!

[tactteam]

I love this series for it's organization and simplicity. There are far too many hour long tutorials on these fundamental concepts. You explain it well and show people it's not as hard as many people make it out to be. Subscribed. Cheers

[fikretsengul]

Hey Mr. Allen, firstly, thank you for everything. I don't know how I discovered you has a wonderful, simple and understandable explanation. I'm a CS student in Ankara Bilkent University. I really wanted to learn swift but it was very complex until I find you. I cannot explain how happy I am, please continue to create these great videos, series and keep it complete and simple. Thank you again. (sorry for the grammar mistakes)

[seanallen]

Have a question about the Do, Try, Catch syntax? Leave a question below!

[soyhenryxyz]

Thanks for putting this example into context. Please continue to do your videos so that it's easier to understand where to use these programming concepts.

[choofie]

Nice explanation Sean! I’m really enjoying your videos! I know it’s crystal clear to everybody, but please note that the magically code that actually logs you in will be performed asynchronously in the background (obviously). So make sure to handle the successful login request properly, and put your transition code there, instead of simply putting them the next line right after try login(). Otherwise the control will be given back to your do block, where the remaining code will be executed before the login response arrives.

[isaacclark]

Thanks for continuing your interview series.

[chrisstromberg]

This was by far one of the best and most practical explanations of Do/Try/Catch I have seen!

[NLBAMF]

my favorite series ... thanks a lot ...

[johntamch]

Another great video from this series! Detailed and yet easy to understand. Thanks.

[tonyferber]

Thank you for the rapid explanation, Do, Try and Catch were confusing me.

I am surprised to see no less than three Bang Operators !

[egesucu]

Well I'm a beginner developer and I really needed to see some videos about iOS development and etc. I found your channel and enjoying so far. Thanks man :)

[ahmedMahmoud-zskn]

Best tutorial ever for swift error handling, really thank you.

[Reel_Sober]

Love your videos man! You are putting out some great content. Thanks for your time and effort.

[Sasan_Soroush]

Your videos are just what i needed all the time
thank you

[martinsin]

Crystal clear of do try catch! Thank you!

[sudebsarkar]

Thanks Sean,
This video is very helpful,
Can you please make sure that if their is any way to write all error cases in another swift file ?
If it is possible, please give an example as I am new in swift so I am facing some problem to write this code.