swift—UIColor十六进制

1：新建一个文件

2.代码

import Foundation
import UIKit

extension UIColor{
    class func colorWithHex(hexStr:String) -> UIColor{
        return UIColor.colorWithHex(hexStr: hexStr, alpha: 1)
    }
}

extension UIColor{
    class func colorWithHex(hexStr:String, alpha:Float) -> UIColor{
        var cStr = hexStr.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines).uppercased() as NSString;
        
        if(cStr.length < 6){
            return UIColor.clear;
        }
        
        if(cStr.hasPrefix("0x")) {
            cStr = cStr.substring(from: 2) as NSString
        }
        
        if(cStr.hasPrefix("#")){
            cStr = cStr.substring(from: 1) as NSString
        }
        
        if(cStr.length != 6){
            return UIColor.clear;
        }
        
        let rStr = (cStr as NSString).substring(to: 2)
        let gStr = ((cStr as NSString).substring(from: 2) as NSString).substring(to: 2)
        let bStr = ((cStr as NSString).substring(from: 4) as NSString).substring(to: 2)
        
        var r : UInt32 = 0x0
        var g : UInt32 = 0x0
        var b : UInt32 = 0x0
        
        Scanner.init(string: rStr).scanHexInt32(&r);
        Scanner.init(string: gStr).scanHexInt32(&g);
        Scanner.init(string: bStr).scanHexInt32(&b);
        
        return UIColor.init(red: CGFloat(r)/255.0, green: CGFloat(g)/255.0, blue: CGFloat(b)/255.0, alpha: CGFloat(alpha));
        
    }
}

3.调用

UIColor.colorWithHex(hexStr: "#2D2D38")
UIColor.colorWithHex(hexStr: "#2D2D38", alpha: 1)

UIColor+hex.swift