hexColor

Posted 2020-07-19 苹果ios开发者

+ (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];
}

// 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 [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:1.0f];
}

+ (UIColor *) colorFromHexCode:(NSString *)hexString {
NSString *cleanString = [hexString stringByReplacingOccurrencesOfString:@"#" withString:@""];
if ([cleanString length] == 3) {
cleanString = [NSString stringWithFormat:@"%@%@%@%@%@%@",
[cleanString substringWithRange:NSMakeRange(0, 1)],[cleanString substringWithRange:NSMakeRange(0, 1)],
[cleanString substringWithRange:NSMakeRange(1, 1)],[cleanString substringWithRange:NSMakeRange(1, 1)],
[cleanString substringWithRange:NSMakeRange(2, 1)],[cleanString substringWithRange:NSMakeRange(2, 1)]];
}
if([cleanString length] == 6) {
cleanString = [cleanString stringByAppendingString:@"ff"];
}

unsigned int baseValue;
[[NSScanner scannerWithString:cleanString] scanHexInt:&baseValue];

float red = ((baseValue >> 24) & 0xFF)/255.0f;
float green = ((baseValue >> 16) & 0xFF)/255.0f;
float blue = ((baseValue >> 8) & 0xFF)/255.0f;
float alpha = ((baseValue >> 0) & 0xFF)/255.0f;

return [UIColor colorWithRed:red green:green blue:blue alpha:alpha];
}