Convert a Hex string to UIColor in Swift

gistfile1.swift

// Creates a UIColor from a Hex string.
func colorWithHexString (hex:String) -> UIColor {
  var cString:String = hex.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet()).uppercaseString
  
  if (cString.hasPrefix("#")) {
    cString = cString.substringFromIndex(1)
  }
  
  if (countElements(cString) != 6) {
    return UIColor.grayColor()
  }
  
  var rString = cString.substringToIndex(2)
  var gString = cString.substringFromIndex(2).substringToIndex(2)
  var bString = cString.substringFromIndex(4).substringToIndex(2)
  
  var r:CUnsignedInt = 0, g:CUnsignedInt = 0, b:CUnsignedInt = 0;
  NSScanner.scannerWithString(rString).scanHexInt(&r)
  NSScanner.scannerWithString(gString).scanHexInt(&g)
  NSScanner.scannerWithString(bString).scanHexInt(&b)
  
  return UIColor(red: Float(r) / 255.0, green: Float(g) / 255.0, blue: Float(b) / 255.0, alpha: Float(1))
}

nice work! @arvidurs

label.textColor = "#007aff".hexColor

in swift 4.0

convenience init(hex: String)
{
let characterSet = NSCharacterSet.whitespacesAndNewlines as! NSMutableCharacterSet
characterSet.formUnion(with: NSCharacterSet.init(charactersIn: "#") as CharacterSet)
let cString = hex.trimmingCharacters(in: characterSet as CharacterSet).uppercased()
if (cString.count != 6) {
self.init(white: 1.0, alpha: 1.0)
} else {
var rgbValue: UInt32 = 0
Scanner(string: cString).scanHexInt32(&rgbValue)

        self.init(red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0,
                  green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0,
                  blue: CGFloat(rgbValue & 0x0000FF) / 255.0,
                  alpha: CGFloat(1.0))
    }
}