ios 如何将十六进制转换为RGB
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how to convert hexadecimal to RGB
提问by R. Dewi
I want to make a conversion from hexadecimal to RGB, but the hexadecimal deal with a string like #FFFFFF. How can I do that?
我想从十六进制转换为 RGB，但十六进制处理像#FFFFFF 这样的字符串。我怎样才能做到这一点？
回答by Matthias Bauch
I've just expanded my UIColor Category for you.
use it like UIColor *green = [UIColor colorWithHexString:@"#00FF00"];
我刚刚为您扩展了我的 UIColor 类别。
像使用它一样UIColor *green = [UIColor colorWithHexString:@"#00FF00"];
//
// UIColor_Categories.h
//
// Created by Matthias Bauch on 24.11.10.
// Copyright 2010 Matthias Bauch. All rights reserved.
//
#import <Foundation/Foundation.h>
@interface UIColor(MBCategory)
+ (UIColor *)colorWithHex:(UInt32)col;
+ (UIColor *)colorWithHexString:(NSString *)str;
@end
//
// UIColor_Categories.m
//
// Created by Matthias Bauch on 24.11.10.
// Copyright 2010 Matthias Bauch. All rights reserved.
//
#import "UIColor_Categories.h"
@implementation UIColor(MBCategory)
// takes @"#123456"
+ (UIColor *)colorWithHexString:(NSString *)str {
const char *cStr = [str cStringUsingEncoding:NSASCIIStringEncoding];
long x = strtol(cStr+1, NULL, 16);
return [UIColor colorWithHex:x];
}
// takes 0x123456
+ (UIColor *)colorWithHex:(UInt32)col {
unsigned char r, g, b;
b = col & 0xFF;
g = (col >> 8) & 0xFF;
r = (col >> 16) & 0xFF;
return [UIColor colorWithRed:(float)r/255.0f green:(float)g/255.0f blue:(float)b/255.0f alpha:1];
}
@end
回答by Andrew Carter
//In your header file
#define UIColorFromRGB(rgbValue) [UIColor colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 green:((float)((rgbValue & 0xFF00) >> 8))/255.0 blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]
//usage
UIColor *color = UIColorFromRGB(0x000000)
//you can also use it inline
[text.textField setTextColor:UIColorFromRGB(0xcccccc)];
回答by Mohamed Jaleel Nazir
Swift
迅速
It is very useful
这是非常有用的
extension UIColor {
convenience init(hexString: String) {
let hex = hexString.trimmingCharacters(in: CharacterSet.alphanumerics.inverted)
var int = UInt32()
Scanner(string: hex).scanHexInt32(&int)
let a, r, g, b: UInt32
switch hex.count {
case 3: // RGB (12-bit)
(a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
case 6: // RGB (24-bit)
(a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF)
case 8: // ARGB (32-bit)
(a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
default:
(a, r, g, b) = (1, 1, 1, 0)
}
self.init(red: CGFloat(r) / 255, green: CGFloat(g) / 255, blue: CGFloat(b) / 255, alpha: CGFloat(a) / 255)
}
public func hexStringWithAlpha(_ includeAlpha: Bool) -> String {
var r: CGFloat = 0
var g: CGFloat = 0
var b: CGFloat = 0
var a: CGFloat = 0
self.getRed(&r, green: &g, blue: &b, alpha: &a)
if (includeAlpha) {
return String(format: "%02X%02X%02X%02X", Int(r * 255), Int(g * 255), Int(b * 255), Int(a * 255))
} else {
return String(format: "%02X%02X%02X", Int(r * 255), Int(g * 255), Int(b * 255))
}
}
open override var description: String {
return self.hexStringWithAlpha(true)
}
open override var debugDescription: String {
return self.hexStringWithAlpha(true)
}
}
Obj-C
对象-C
UIColor *organizationColor = [self colorWithHexString:@"#ababab" alpha:1];
- (UIColor *)colorWithHexString:(NSString *)str_HEX alpha:(CGFloat)alpha_range{
int red = 0;
int green = 0;
int blue = 0;
sscanf([str_HEX UTF8String], "#%02X%02X%02X", &red, &green, &blue);
return [UIColor colorWithRed:red/255.0 green:green/255.0 blue:blue/255.0 alpha:alpha_range];
}
