iOS十六进制转RGB

/**
 16进制颜色转换为UIColor

 @param hexColor 16进制字符串（可以以0x开头，可以以#开头，也可以就是6位的16进制）
 @return 16进制字符串对应的颜色
 */
+(UIColor *)colorWithHexString:(NSString *)hexColor{
    
    NSString *cString = [[hexColor stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];

    if ([cString length] < 6) return [UIColor blackColor];

    if ([cString hasPrefix:@"0X"]) cString = [cString substringFromIndex:2];
    if ([cString hasPrefix:@"#"]) cString = [cString substringFromIndex:1];

    if ([cString length] != 6) return [UIColor blackColor];

    NSString *rString = [cString substringWithRange:NSMakeRange(0, 2)];
    NSString *gString = [cString substringWithRange:NSMakeRange(2, 2)];
    NSString *bString = [cString substringWithRange:NSMakeRange(4, 2)];

    unsigned int r, g, b;  // Scan values
    
    [[NSScanner scannerWithString:rString] scanHexInt:&r];
    [[NSScanner scannerWithString:gString] scanHexInt:&g];
    [[NSScanner scannerWithString:bString] scanHexInt:&b];

    return [UIColor colorWithRed:((float)r / 255.0f)
                           green:((float)g / 255.0f)
                            blue:((float)b / 255.0f)
                           alpha:1];
}