Hello, in this video, we are going to look at exception handling and Exception Handling something that I would definitely recommend doing. Now a lot of beginners do sort of bottom, they just don't do I even know really good developers that, you know, don't do in that basic question. Are they good developers or not? So Exception Handling? Well, yeah, allowed to handle any problems that may arise. And, you know, trust me, probably not gonna rise, especially when you've got user interaction there, they'll definitely be problems with that.
Okay, next thing, the reason I'm doing it on a local environment and multi regular online environment is to demonstrate one of the exception handling functionality, I want to actually try and open up a file and you need to be on to a local environment to be able to do that. So Otherwise, the other like, the code will work online if you aren't doing Exception Handling for like filing but it's just you know, that's one of the easiest ones to do. So the first thing We're going to do is create a method. So to create a function, I'm gonna call it function one. And I'll pass it in a parameter. I'll call it bar one.
All the stuff so far, we'll have a return statement, and this will return. The way I'm gonna do is I'm gonna return 10 divided by 10 divided by 10 divided by one. Okay, so that's all good stuff so far. And if I print this out for printed function, one, and I'll just pass in five, for example, that should yield a result to save it. Module. There we go.
Guess as to Not all good stuff. lira though. We know what's gonna happen you know division by zero, you know, that can't be done in math, mathematics. So, we could do any statement or you know not an easy way is to do is use an assert statement. So assert and witness asserting what is valid and what is not valid. So we want to check if while one is not equal to zero, then we would continue to save it.
We need a second parameter which is just a value saying something to the user. Now, something's gone wrong. So, zero invalid before we run this Okay, what's the problem? Ah sorry, should be zero. That's what we check in. Oh checking if he wasn't equal to do what is going on?
Now we're up done. I've messed up the bracket, bracket brackets must be there. Now the actual thing that you want to say to the user zero is a valid as you can see the assert has now been hit. If I put in a value of four for example, you should give us a result two and a half. You know, works. The assert just the beauty of you know, concert is you check in as well.
So it's not just an error being thrown, you're doing a check. So the actual error is a bit more contextual, when you have a lot of code and no loss of governing bill. Okay, I understand there have been more why that has happened. So there's something called exception if you would like to try catch block in many other languages. I'm going to demonstrate it by trying to open up a file. So I'll put it up to no, this is valid so far.
Very similar to this, then you can think of it pretty similar. And the try block, you do try and do now you put the code that you will actually try to do so if I say file equals open, so I want to try and open some file Open up text dot txt W and now it's on file dot write. We want to write something Hello. Now what we want to do is specified to some sort of input output everything except IO error. Make sure you sort out the indentation properly print and we're just going to say following up while and there will be announcing. The aos is just you know everything you know He is fine.
So you will just do you don't have to work for Apple. Okay? And they obviously want to kill your father. So if I rerun this now and we get a, okay because it was successfully able to create the file, but if something went wrong maybe the OS, you know, interrupted it in some capacity and said, you know, you can create a file here maybe we'll read only for example there a particular directory was then this would have been triggered and it was said file not found. And if less we had a number mode, which was for reading for example, and you know, you put an action create the for the next task going to you know, do that, then it would get into the Excel as well. So that's the Except to block and very similar to the try catch block as well.
There's more functionality within exceptions. But if you understand what we've covered in this video, then honestly, you're good to go. And if you have any questions, feel free to reach out. There'll be a link in the description, linking you with more of the functionality around exception handling. And I look forward to seeing you in the next video. Thanks for watching, and I'll see you then.