by Oliver
22. September 2016 01:02
When I validate forms, I usually don't want the user to allow to enter only whitespace in any of the text fields that I deem required. With a handful of them, checking for that condition can be annoying.
Let me introduce you to… TrimTextBox!
To centralize the concern to trim padding whitespace from text inputs, I simply derived from the built-in TextBox class and overrode a single property – Text:
With this simple piece of code my backend validation logic can now focus on the business rules, e.g. a minimum length of one character, without having to worry about leading, trailing, or only whitespace in any input field.
Don't Repeat Yourself – Keep it DRY
Whenever I encounter a piece of code that repeats more than once, I try and refactor that code away to make it reusable and sometimes even to completely hide a certain aspect of it from the current context so that when reading a block of code I can decide whether I want to dive deeper into the nitty gritty details or just get an overview of the workflow I'm looking at. This saves my brain some precious resources ;-)
I wonder what other use cases you can come up with where a specialized control can make your developer life simpler :-)
Happy coding (subclassing)!