How to read a single character from a string
Swift version: 5.2
Swift’s strings are stored in a specific way that stops you from indexing into then easily. In fact, reading one letter from part-way through the string means starting at the beginning of the string and counting through letters until you find the one you want, so if you try reading all the characters in the string this way you could accidentally create extremely slow code.
However, if you only need to read one or two letters, here’s a simple extension on String that will help:
extension String {
subscript(i: Int) -> String {
return String(self[index(startIndex, offsetBy: i)])
}
}With that place in place, you can write myString[15] to read the 16th letter.
SPONSORED Building and maintaining in-app subscription infrastructure is hard. Luckily there's a better way. With RevenueCat, you can implement subscriptions for your app in hours, not months, so you can get back to building your app.
Sponsor Hacking with Swift and reach the world's largest Swift community!
Available from iOS 8.0
Similar solutions…
- Optional vs implicitly unwrapped optional: what’s the difference?
- How to add drag and drop to your app
- How to convert dates and times to a string using DateFormatter
- How to handle unknown properties and methods using @dynamicMemberLookup
- How to calculate the ROT13 of a string
About the Swift Knowledge Base
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
