You should always validate data entered by user or received from backend before doing any processing on it, for example if you are expecting a string object that contains a price or quantity then this string must include only digits.
In iOS UIAlertController is not only used to output messages to user but it can also accept input text from the user.
In this tutorial we will learn how to add UITextField to UIAlertController so lets start
Presenting a long list of items to user may not be a good decision because you will have the user keep scrolling till he finds what he is looking for, instead you can group these items in sections for ease of navigation.Dictionary introduce a simple method for grouping objects of . . . Read more
Learn how to display an alert message to the user in iOS using UIAlertController
What are escaping closures in Swift and how to use them
guard statement is one of three branch statements in Swift, the if statement, guard statement and switch statement.