颜色转换

+ (UIColor *) colorWithHexString: (NSString *) stringToConvert

{

?

? ? NSString *cString = [[stringToConvert stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] uppercaseString];

?

? ? // String should be 6 or 8 characters

? ? if ([cString length] < 6) return nil;

?

? ? // strip 0X if it appears

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

? ? if ([cString hasPrefix:@"#"]) cString = [cString substringFromIndex:1];

? ? if ([cString length] != 6) return nil;

? ? // Separate into r, g, b substrings

? ? NSRange range;

? ? range.location = 0;

? ? range.length = 2;

? ? 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];

}