Get the length of a String

Question

How do you get the length of a String? For example, I have a variable defined like:

var test1: String = "Scott"

However, I can't seem to find a length method on the string.

Answer 1

If you are just trying to see if a string is empty or not (checking for length of 0), Swift offers a simple boolean test method on String

myString.isEmpty

The other side of this coin was people asking in ObjectiveC how to ask if a string was empty where the answer was to check for a length of 0:

NSString is empty

Answer 2

String and NSString are toll free bridge so you can use all methods available to NSString with swift String

let x = "test" as NSString
let y : NSString = "string 2"
let lenx = x.count
let leny = y.count

Answer 3

Swift 4 update comparing with swift 3

Swift 4 removes the need for a characters array on String. This means that you can directly call count on a string without getting characters array first.

"hello".count                  // 5

Whereas in swift 3, you will have to get characters array and then count element in that array. Note that this following method is still available in swift 4.0 as you can still call characters to access characters array of the given string

"hello".characters.count       // 5

Swift 4.0 also adopts Unicode 9 and it can now interprets grapheme clusters. For example, counting on an emoji will give you 1 while in swift 3.0, you may get counts greater than 1.

"                                                                    

                                                        
            

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Answer 4

in Swift 2.x the following is how to find the length of a string

let findLength = "This is a string of text"
findLength.characters.count

returns 24

Answer 5

Here is what I ended up doing

let replacementTextAsDecimal = Double(string)

if string.characters.count > 0 &&
    replacementTextAsDecimal == nil &&
    replacementTextHasDecimalSeparator == nil {
        return false
}

Answer 6

For XCode 7.3 and Swift 2.2.

let str = "                                                                    

                                                        
            

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