Determining if swift string contains emoji character

gistfile1.swift

func containsEmoji(text: String) -> Bool {
    var containsEmoji = false
    for scalar in text.unicodeScalars {
        switch scalar.value {
        case 0x1F600...0x1F64F:
            // Emoticons
            containsEmoji = true
        case 0x1F300...0x1F5FF:
            // Misc Symbols and Pictographs
            containsEmoji = true
        case 0x1F680...0x1F6FF:
            // Transport and Map
            containsEmoji = true
        case 0x2600...0x26FF:
            // Misc symbols, not all emoji
            containsEmoji = true
        case 0x2700...0x27BF:
            // Dingbats, not all emoji
            containsEmoji = true
        default: ()
        }
    }
    return containsEmoji
}