Convert Int To String

Question

Oscar314 OP

Created Mar ’18

Replies 2

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For example, I want the value (for the purpose of a label) to display "." at one stage and a number a different stage.

Answered by QuinceyMorris in 300233022

You have lots of options:

     let n = 42
     let s1 = String (n)
     let s2 = "\(n)"
     let s3 = String (format: "%d", n)
     let s4 = NumberFormatter ().string (for: n)

Note that the third case (using a string format) is a bit treacherous if Int is 32 bits rather than 64 bits, but I don't think there are any current Apple platforms where it is 32 bits. Using a format is useful is you want to use a specifier that controls the number of digits displayed, padding, etc.

The fourth case is useful if you want localized formatting of the number.

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Answer 1

QuinceyMorris OP

Mar ’18

Accepted Answer

You have lots of options:

     let n = 42
     let s1 = String (n)
     let s2 = "\(n)"
     let s3 = String (format: "%d", n)
     let s4 = NumberFormatter ().string (for: n)

Note that the third case (using a string format) is a bit treacherous if Int is 32 bits rather than 64 bits, but I don't think there are any current Apple platforms where it is 32 bits. Using a format is useful is you want to use a specifier that controls the number of digits displayed, padding, etc.

The fourth case is useful if you want localized formatting of the number.

0

Answer 2

DTS Engineer OP

Apple

Mar ’18

I don't think there are any current Apple platforms where it is 32 bits.

That’s not quite true; watchOS is the last holdout.

The fourth case is useful if you want localized formatting of the number.

In that case you’re better off doing this:

let s4 = NumberFormatter.localizedString(from: n as NSNumber, number: .decimal)

Formatters tend to be heavyweight objects, so it’s better to cache them, and this convenience method does that caching for you.

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