594
votes

I'm trying to work out how to cast an Int into a String in Swift.

I figure out a workaround, using NSNumber but I'd love to figure out how to do it all in Swift.

let x : Int = 45
let xNSNumber = x as NSNumber
let xString : String = xNSNumber.stringValue
23

23 Answers

1025
votes

Converting Int to String:

let x : Int = 42
var myString = String(x)

And the other way around - converting String to Int:

let myString : String = "42"
let x: Int? = myString.toInt()

if (x != nil) {
    // Successfully converted String to Int
}

Or if you're using Swift 2 or 3:

let x: Int? = Int(myString)
93
votes

Check the Below Answer:

let x : Int = 45
var stringValue = "\(x)"
print(stringValue)
61
votes

Here are 4 methods:

var x = 34
var s = String(x)
var ss = "\(x)"
var sss = toString(x)
var ssss = x.description

I can imagine that some people will have an issue with ss. But if you were looking to build a string containing other content then why not.

54
votes

In Swift 3.0:

var value: Int = 10
var string = String(describing: value)
27
votes

Just for completeness, you can also use:

let x = 10.description

or any other value that supports a description.

27
votes

Swift 4:

let x:Int = 45
let str:String = String(describing: x)

Developer.Apple.com > String > init(describing:)

The String(describing:) initializer is the preferred way to convert an instance of any type to a string.

Custom String Convertible

enter image description here

11
votes

Swift 4:

Trying to show the value in label without Optional() word.

here x is a Int value using.

let str:String = String(x ?? 0)
8
votes

To save yourself time and hassle in the future you can make an Int extension. Typically I create a shared code file where I put extensions, enums, and other fun stuff. Here is what the extension code looks like:

extension Int
{
    func toString() -> String
    {
        var myString = String(self)
        return myString
    }
}

Then later when you want to convert an int to a string you can just do something like:

var myNumber = 0
var myNumberAsString = myNumber.toString()
8
votes

in swift 3.0 this is how we can convert Int to String and String to Int

//convert Integer to String in Swift 3.0

let theIntegerValue :Int = 123  // this can be var also
let theStringValue :String = String(theIntegerValue)


//convert String to Integere in Swift 3.0


let stringValue : String = "123"
let integerValue : Int = Int(stringValue)!
7
votes

for whatever reason the accepted answer did not work for me. I went with this approach:

var myInt:Int = 10
var myString:String = toString(myInt)
5
votes

Multiple ways to do this :

var str1:String="\(23)"
var str2:String=String(format:"%d",234)
4
votes

Swift 2:

var num1 = 4
var numString = "56"
var sum2 = String(num1) + numString
var sum3 = Int(numString)
2
votes

iam using this simple approach

String to Int:

 var a = Int()
var string1 = String("1")
a = string1.toInt()

and from Int to String:

var a = Int()
a = 1
var string1 = String()
 string1= "\(a)"
2
votes

Convert Unicode Int to String

For those who want to convert an Int to a Unicode string, you can do the following:

let myInteger: Int = 97

// convert Int to a valid UnicodeScalar
guard let myUnicodeScalar = UnicodeScalar(myInteger) else {
    return ""
}

// convert UnicodeScalar to String
let myString = String(myUnicodeScalar)

// results
print(myString) // a

Or alternatively:

let myInteger: Int = 97
if let myUnicodeScalar = UnicodeScalar(myInteger) {
    let myString = String(myUnicodeScalar)
}
1
votes

exampleLabel.text = String(yourInt)

1
votes

I prefer using String Interpolation

let x = 45
let string = "\(x)"

Each object has some string representation. This makes things simpler. For example if you need to create some String with multiple values. You can also do any math in it or use some conditions

let text = "\(count) \(count > 1 ? "items" : "item") in the cart. Sum: $\(sum + shippingPrice)"
0
votes

To convert String into Int

var numberA = Int("10")

Print(numberA) // It will print 10

To covert Int into String

var numberA = 10

1st way)

print("numberA is \(numberA)") // It will print 10

2nd way)

var strSomeNumber = String(numberA)

or

var strSomeNumber = "\(numberA)"
0
votes
let a =123456888
var str = String(a)

OR

var str = a as! String
0
votes

In swift 3.0, you may change integer to string as given below

let a:String = String(stringInterpolationSegment: 15)

Another way is

let number: Int = 15
let _numberInStringFormate: String = String(number)

//or any integer number in place of 15

0
votes

If you like swift extension, you can add following code

extension Int
{
    var string:String {
        get {
            return String(self)
        }
    }
}

then, you can get string by the method you just added

var x = 1234
var s = x.string
0
votes

A little bit about performance UI Testing Bundle on iPhone 7(real device) with iOS 14

let i = 0
lt result1 = String(i) //0.56s 5890kB
lt result2 = "\(i)" //0.624s 5900kB
lt result3 = i.description //0.758s 5890kB
import XCTest

class ConvertIntToStringTests: XCTestCase {

    let count = 1_000_000
    
    func measureFunction(_ block: () -> Void) {
        
        let metrics: [XCTMetric] = [
            XCTClockMetric(),
            XCTMemoryMetric()
        ]
        let measureOptions = XCTMeasureOptions.default
        measureOptions.iterationCount = 5
        
        measure(metrics: metrics, options: measureOptions) {
            block()
        }
    }

    func testIntToStringConstructor() {
        var result = ""
        
        measureFunction {
            
            for i in 0...count {
                result += String(i)
            }
        }

    }
    
    func testIntToStringInterpolation() {
        var result = ""
        
        measureFunction {
            for i in 0...count {
                result += "\(i)"
            }
        }
    }
    
    func testIntToStringDescription() {
        var result = ""
        measureFunction {
            for i in 0...count {
                result += i.description
            }
        }
    }
}
-1
votes
let Str = "12"
let num: Int = 0
num = Int (str)
-1
votes
let intAsString = 45.description     // "45"
let stringAsInt = Int("45")          // 45