A view of a string’s contents as a collection of Unicode scalar values.
SDK
- Xcode 6.0.1+
Framework
- Swift Standard Library
Declaration
@frozen struct UnicodeScalarView
Overview
You can access a string’s view of Unicode scalar values by using its unicode property. Unicode scalar values are the 21-bit codes that are the basic unit of Unicode. Each scalar value is represented by a Unicode instance and is equivalent to a UTF-32 code unit.
let flowers = "Flowers 💐"
for v in flowers.unicodeScalars {
print(v.value)
}
// 70
// 108
// 111
// 119
// 101
// 114
// 115
// 32
// 128144
Some characters that are visible in a string are made up of more than one Unicode scalar value. In that case, a string’s unicode view contains more elements than the string itself.
let flag = "🇵🇷"
for c in flag {
print(c)
}
// 🇵🇷
for v in flag.unicodeScalars {
print(v.value)
}
// 127477
// 127479
You can convert a String instance back into a string using the String type’s init(_:) initializer.
let favemoji = "My favorite emoji is 🎉"
if let i = favemoji.unicodeScalars.firstIndex(where: { $0.value >= 128 }) {
let asciiPrefix = String(favemoji.unicodeScalars[..<i])
print(asciiPrefix)
}
// Prints "My favorite emoji is "