swift 中利用UIColor擴充套件建立16進位制轉UIColor類如下：

程式碼如下：

extension UIColor {

    class func hexStringToColor(hexString: String) -> UIColor{

        var cString: String = hexString.trimmingCharacters(in: NSCharacterSet.whitespacesAndNewlines)

        if cString.characters.count < 6 {
            return UIColor.black
 

        }
        if cString.hasPrefix("0X") {
            cString = cString.substring(from: cString.index(cString.startIndex, offsetBy: 2))
        }
        if cString.hasPrefix("#") {
            cString = cString.substring(from: cString.index(cString.startIndex, offsetBy: 1))
        }
        if cString.characters
 
.count != 6 {
            return UIColor.black
        }

        var range: NSRange = NSMakeRange(0, 2)
        let rString = (cString as NSString).substring(with: range)
        range.location = 2
        let gString = (cString as NSString).substring(with: range)
        range.location = 4
        let bString = (cString as NSString).substring
 
(with: range)

        var r: UInt32 = 0x0
        var g: UInt32 = 0x0
        var b: UInt32 = 0x0
        Scanner.init(string: rString).scanHexInt32(&r)
        Scanner.init(string: gString).scanHexInt32(&g)
        Scanner.init(string: bString).scanHexInt32(&b)

        return UIColor(displayP3Red: CGFloat(r)/255.0, green: CGFloat(g)/255.0, blue: CGFloat(b)/255.0, alpha: CGFloat(1))

    }
}