Is there a way to check if a character belongs to a CharacterSet?
I wanna know what CharacterSet should I use for character -. Do I use symbols?
I've checked this documentation but still no idea. https://developer.apple.com/documentation/foundation/characterset
When removing extra whitespace at the end of a string, we do it like this:
let someString = " "
print("\(11111) - \(someString)".trimmingCharacters(in: .whitespaces))
But what if I just want to remove the -? Or any special character such as *?
EDIT: I was looking for a complete set of characters per each CharacterSet if it's possible.
What you want is defined in the Unicode standard. It is referred to as Unicode General Categories. Each Unicode character is in a category.
The Unicode website provides a complete character list showing the character's code, category, and name. You can also find a complete list of Unicode categories as well.
The - is U+2D (HYPHEN-MINUS). It is listed as being in the "Pd" (punctuation) category.
If you look at the documentation for CharacterSet, you will see punctuationCharacters which is documented as:
Returns a character set containing the characters in Unicode General Category P*.
The "Pd" category is included in "P*" (which means any "P" category).
I also found https://www.compart.com/en/unicode/category which is a third party list of each character by category. A bit more user friendly than the Unicode reference.
To summarize. If you want to know which CharacterSet to use for a given character, lookup the character's category using one of the charts I linked. Once you know its category, look at the documentation for CharacterSet to see which predefined character set applies to that category.