ios 十六进制颜色转换成RGB

#import 

@interface UIColor (ColorChange)


/**
 * 方法描述：透明度固定为1，以0x开头的十六进制转换
 *
 * @param hexColor 0x开头的十六进制
 * @return UIColor(RGB)
 *
 */
+ (UIColor *)colorWithHex:(long)hexColor;

/**
 * 方法描述：0x开头的十六进制转换,透明度可调整
 *
 * @param hexColor 0x开头的十六进制
 * @param opacity 透明度可设
 * @return UIColor(RGB)
 *
 */
+ (UIColor *)colorWithHex:(long)hexColor alpha:(float)opacity;

/**
 * 方法描述：以#开头的十六进制的颜色转换成的颜色
 *
 * @param color #开头的十六进制
 * @return UIColor(RGB)
 */
+ (UIColor *)colorWithHexString:(NSString *)color;

@end

 

#import "UIColor+ColorChange.h"

@implementation UIColor (ColorChange)

// 透明度固定为1，以0x开头的十六进制转换成的颜色
+ (UIColor *)colorWithHex:(long)hexColor;
{
    return [UIColor colorWithHex:hexColor alpha:1.];
}

// 0x开头的十六进制转换成的颜色,透明度可调整
+ (UIColor *)colorWithHex:(long)hexColor alpha:(float)opacity
{
    float red = ((float)((hexColor & 0xFF0000) >> 16))/255.0;
    float green = ((float)((hexColor & 0xFF00) >> 8))/255.0;
    float blue = ((float)(hexColor & 0xFF))/255.0;
    
    return [UIColor colorWithRed:red green:green blue:blue alpha:opacity];
}

// 以#开头的十六进制的颜色转换为UIColor
+ (UIColor *) colorWithHexString: (NSString *)color
{
    NSString *cString = [[color stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];
    
    // String should be 6 or 8 characters
    if ([cString length] < 6)
    {
        return [UIColor clearColor];
    }
    
    // 判断前缀
    if ([cString hasPrefix:@"0X"])
        cString = [cString substringFromIndex:2];
    if ([cString hasPrefix:@"#"])
        cString = [cString substringFromIndex:1];
    if ([cString length] != 6)
        return [UIColor clearColor];
    
    // 从六位数值中找到RGB对应的位数并转换
    NSRange range;
    range.location = 0;
    range.length = 2;
    
    // R、G、B
    NSString *rString = [cString substringWithRange:range];
    range.location = 2;
    NSString *gString = [cString substringWithRange:range];
    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:1.0f];
}