Styjun

I have to do validation to check user entered answer to an application. I want to remove spaces (if any) left or before for bellow special characters.

• 
  /


• 
  ,


• 
  :


• 
  ;


• -


• .

So the final output should be like this.

Ex:

Correct answer => a/b

Answers need to accept => ' a/b ', 'a/ b', 'a /b', 'a/ b ', 'a/b '

I can do this using replacingOccurrences function by replacing all possible values. Is there any better solution for this?

You can using regular expression for replace the string with format [ ]+special_char and special_char[ ]+.

Edit

Update "." to "\."

Thanks ielyamani

For example

func acceptedAnswer(of answer: String) -> String 
 let specialChars = ["/", ":", ",", ";", "-", "\."]
 var newAnswer = answer.trimmingCharacters(in: .whitespacesAndNewlines)
 for specialChar in specialChars 
 let beforeCharRegex = "[ ]+" + specialChar
 let afterCharRegex = specialChar + "[ ]+"
 newAnswer = newAnswer.replacingOccurrences(of: beforeCharRegex, with: specialChar, options: .regularExpression, range: nil)
 newAnswer = newAnswer.replacingOccurrences(of: afterCharRegex, with: specialChar, options: .regularExpression, range: nil)
 
 return newAnswer


print(acceptedAnswer(of: " apple / orange : banana "))
// apple/orange:banana

Remove before and after space of Special character using Range -

 let specialChars = ["/",":", ",", ";", "-", "."]
 let aString = " AB / CD EF ; G : H , MN O - P"
 var trimmedString = aString.trimmingCharacters(in: .whitespacesAndNewlines)

 for specialChar in specialChars 

 if let beforeSpacerange = trimmedString.range(of: " (specialChar)") 
 trimmedString.replaceSubrange(beforeSpacerange, with: specialChar)
 
 if let afterSpacerange = trimmedString.range(of: "(specialChar) ") 
 trimmedString.replaceSubrange(afterSpacerange, with: specialChar)
 

 

 debugPrint(trimmedString)

Hope it will help you. Let me know if you are still having any issue.

Happy coding.

You can use replacingOccurrences which would replace your symbol with whitespaces with just this symbol. For this purpose you can use recursive method

func removed(in text: String) -> String 
 let symbols = ["/", ",", ":", ";", "-", "."]
 var newText = text
 symbols.forEach newText = replaced(in: newText, for: $0) 
 return newText


func replaced(in text: String, for symbol: String) -> String 
 var newText = text
 let left = " (symbol)"
 newText = newText.replacingOccurrences(of: left, with: symbol)
 let right = "(symbol) "
 newText = newText.replacingOccurrences(of: right, with: symbol)
 return newText != text ? replaced(in: newText, for: symbol) : newText

Usage:

let string = "Apple / Orange Swift . ObjC Moon : Sun USA - UK"
print(removed(in: string))

Apple/Orange Swift.ObjC Moon:Sun USA-UK