How to capitalize the first letter of a string

Swift version: 5.1

Paul Hudson    @twostraws    May 28th 2019

If you want to capitalize the first letter of a string without touching the rest of the letters, add this simple extension of String:

extension String {
    func capitalizingFirstLetter() -> String {
        return prefix(1).capitalized + dropFirst()
    }

    mutating func capitalizeFirstLetter() {
        self = self.capitalizingFirstLetter()
    }
}

Here’s an example to try it out:

let test = "the rain in Spain"
print(test.capitalizingFirstLetter())

Available from iOS 8.0

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