//
//  UIColor+Hex.h
//
//  Created by GD on 17/2/28.
//  Copyright ? 2016年 LyLiveApp. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UIColor (Hex)

+ (UIColor *)colorWithHexString:(NSString *)color;

//從十六進制字符串獲取顏色掂名，
//color:支持@“#123456”肺孵、 @“0X123456”损趋、 @“123456”三種格式
+ (UIColor *)colorWithHexString:(NSString *)color alpha:(CGFloat)alpha;

@end

//
//  UIColor+Hex.m
//
//  Created by GD on 17/2/28.
//  Copyright ? 2016年 LyLiveApp. All rights reserved.
//

#import "UIColor+Hex.h"

@implementation UIColor (Hex)

+ (UIColor *)colorWithHexString:(NSString *)color alpha:(CGFloat)alpha
{
    //刪除字符串中的空格
    NSString *cString = [[color stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];
    // String should be 6 or 8 characters
    if ([cString length] < 6)
    {
        return [UIColor clearColor];
    }
    // strip 0X if it appears
    //如果是0x開頭的岂贩，那么截取字符串崔慧，字符串從索引為2的位置開始，一直到末尾
    if ([cString hasPrefix:@"0X"])
    {
        cString = [cString substringFromIndex:2];
    }
    //如果是#開頭的室奏，那么截取字符串谬墙，字符串從索引為1的位置開始，一直到末尾
    if ([cString hasPrefix:@"#"])
    {
        cString = [cString substringFromIndex:1];
    }
    if ([cString length] != 6)
    {
        return [UIColor clearColor];
    }
    
    // Separate into r, g, b substrings
    NSRange range;
    range.location = 0;
    range.length = 2;
    //r
    NSString *rString = [cString substringWithRange:range];
    //g
    range.location = 2;
    NSString *gString = [cString substringWithRange:range];
    //b
    range.location = 4;
    NSString *bString = [cString substringWithRange:range];
    
    // Scan values
    unsigned int r, g, b;
    [[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:alpha];
}

//默認alpha值為1
+ (UIColor *)colorWithHexString:(NSString *)color
{
    return [self colorWithHexString:color alpha:1.0f];
}

@end