How to append a character to a string in Swift?

Question

This used to work in Xcode 6: Beta 5. Now I'm getting a compilation error in Beta 6.

for aCharacter: Character in aString {
    var str: String = ""
    var newStr: String = str.append(aCharacter) // ERROR
    ...
}

Error: Cannot invoke append with an argument of type Character

Yep. That was the original syntax I used and gave this error: cannot invoke '+' with an argument list of type '(Character, @lvalue String)' — samatron, Aug 23 '14 at 02:52

Gary Makin · Accepted Answer · 2016-02-17T00:50:01.257

44

Update for the moving target that is Swift:

Swift no longer has a + operator that can take a String and an array of characters. (There is a string method appendContentsOf() that can be used for this purpose).

The best way of doing this now is Martin R’s answer in a comment below:

var newStr:String = str + String(aCharacter)

Original answer: This changed in Beta 6. Check the release notes.I'm still downloading it, but try using:

var newStr:String = str + [aCharacter]

edited Feb 17 '16 at 00:50

answered Aug 23 '14 at 01:41

Gary Makin

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Thanks that worked. I guess I'm suppose to infer that an array of characters is a string? No mention of this specific syntax in release notes for Beta 6. – samatron Aug 23 '14 at 02:54
1

It could have been clearer but it does say "You can still + two Characters or a String with any other sequence of Character or an Array with any other sequence of the same element type." From that, I decided to make the character into an array with the [] syntax. – Gary Makin Aug 23 '14 at 03:00
8

`var newStr:String = str + String(aCharacter)` works as well. – Martin R Aug 23 '14 at 04:42
Above answer returns `'String' is not identical to 'Uint8'`. I guess the latest official version is different to the beta used by Gary. So the right answer seems to be that of Martin R. – qwerty_so Nov 24 '14 at 07:35
I'm not sure what you're doing to get `'String' is not identical to 'Uint8'` but I agree that Martin's answer will be correct in more circumstances. – Gary Makin Jan 20 '15 at 23:33

score 11 · Answer 2 · answered Mar 17 '15 at 19:00

11

This also works

var newStr:String = str + String(aCharacter)

answered Mar 17 '15 at 19:00

baskInEminence

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26

1

...and I would say is the 'Swifter' way to do it. – Grimxn Aug 16 '15 at 08:49

Mike Vosseller · Answer 3 · 2015-08-16T16:27:08.263

9

append append(c: Character) IS the right method but your code has two other problems.

The first is that to iterate over the characters of a string you must access the String.characters property.

The second is that the append method doesn't return anything so you should remove the newStr.

The code then looks like this:

for aCharacter : Character in aString.characters {
    var str:String = ""
    str.append(aCharacter)
    // ... do other stuff
}

edited Aug 16 '15 at 16:27

answered Aug 15 '15 at 23:59

Mike Vosseller

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right, just setting up a loop like the OP. Added do other stuff comment – Mike Vosseller Aug 16 '15 at 16:27

score 5 · Answer 4 · answered Aug 16 '15 at 08:40

5

Another possible option is

var s: String = ""
var c: Character = "c"
s += "\(c)"

answered Aug 16 '15 at 08:40

hennes

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score 2 · Answer 5 · answered Jan 18 '18 at 22:48

According to Swift 4 Documentation , You can append a Character value to a String variable with the String type’s append() method:

var welcome = "hello there"

let exclamationMark: Character = "!"
welcome.append(exclamationMark)
// welcome now equals "hello there!"

score 1 · Answer 6 · answered Aug 16 '15 at 08:45

1

var stringName: String = "samontro"
var characterNameLast: Character = "n"
stringName += String(characterNameLast) // You get your name "samontron"

answered Aug 16 '15 at 08:45

user3182143

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score 0 · Answer 7 · answered Oct 08 '17 at 14:32

I had to get initials from first and last names, and join them together. Using bits and pieces of the above answers, this worked for me:

  var initial: String = ""

            if !givenName.isEmpty {
                let char = (givenName as NSString).substring(with: NSMakeRange(0, 1))
               let str = String(char)
                initial.append(str)
            }

            if !familyName.isEmpty {
                 let char = (familyName as NSString).substring(with: NSMakeRange(0, 1))
                let str = String(char)
                initial.append(str)
            }

score 0 · Answer 8 · answered Sep 23 '21 at 07:18

0

for those looking for swift 5, you can do interpolation.

var content = "some random string"
content = "\(content)!!"
print(content) // Output: some random string!!

answered Sep 23 '21 at 07:18

Jiraheta

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score -1 · Answer 9 · edited Aug 30 '17 at 10:08

-1

 let original:String = "Hello"
 var firstCha = original[original.startIndex...original.startIndex]

 var str = "123456789"
 let x = (str as NSString).substringWithRange(NSMakeRange(0, 4))

 var appendString1 = "\(firstCha)\(x)" as String!
 // final name
 var namestr = "yogesh"
 var appendString2 = "\(namestr) (\(appendString1))" as String!*

edited Aug 30 '17 at 10:08

Raksha Saini

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answered Sep 30 '15 at 05:55

Yogesh shelke

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How to append a character to a string in Swift?

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