随机颜色

//  UIColor+Hex.m创建继承于UIColor的类别 随机颜色

---

UIColor+Hex.h

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

---

UIColor+Hex.m

//  UIColorDemo

#import"UIColor+Hex.h"

#define RGBCOLOR(r,g,b) [UIColor colorWithRed:r/255.0green:g/255.0blue:b/255.0alpha:1]

@implementation UIColor (Hex)

+ (UIColor *)colorWithHexString:(NSString *)hexSting {

//修剪字符串去掉其中的特殊字符和空格

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

//#55DDBB 55->R DD->G BB->B长度小于6不符合要求

if([cStringlength] < 6) {

return[UIColor clearColor];

}

//如果是0X开头,那么从第二个字符开始剪切字符串

if([cString hasPrefix:@"0X"]) {

cString = [cString substringFromIndex:2];

}

//如果是以#开头,那么从第一个字符开始剪切字符串

if([cString hasPrefix:@"#"]) {

cString = [cString substringFromIndex:1];

}

//如果剪切到的字符串长度不是6也不符合要求

if([cString length] != 6) {

return[UIColor clearColor];

}

//0123456789ABCDEF字符集

//超出字符集不可使用

NSCharacterSet *hexSet = [NSCharacterSet characterSetWithCharactersInString:@"0123456789ABCDEF"];

NSRange range;

range.location= 0;

range.length= 2;

NSString *rString = [cString substringWithRange:range];

NSCharacterSet *rSet = [NSCharacterSet characterSetWithCharactersInString:rString];

range.location= 2;

NSString *gString = [cString substringWithRange:range];

NSCharacterSet *gSet = [NSCharacterSet characterSetWithCharactersInString:gString];

range.location= 4;

NSString *bString = [cString substringWithRange:range];

NSCharacterSet *bSet = [NSCharacterSet characterSetWithCharactersInString:bString];

if(![hexSetisSuper setOfSet:rSet] || ![hexSetisSuper setOfSet:gSet] || ![hexSetisSuper setOfSet:bSet]) {

return[UIColor clearColor];

}

unsigned int r,g,b;

[[NSScanner scannerWithString:rString] scanHexInt:&r];

[[NSScanner scannerWithString:gString] scanHexInt:&g];

[[NSScanner scannerWithString:bString] scanHexInt:&b];

return RGBCOLOR(r, g, b);

}