UIColor之【扩展：#FFFFFF ->UIColor】

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

if ([hexColor length] == 7 && [hexColor hasPrefix:@"#"]) {

unsigned int red, green, blue;
NSRange range;
range.length = 2;

range.location = 1;
[[NSScanner scannerWithString:[hexColor substringWithRange:range]]scanHexInt:&red];

range.location = 3;
[[NSScanner scannerWithString:[hexColor substringWithRange:range]]scanHexInt:&green];

range.location = 5;
[[NSScanner scannerWithString:[hexColor substringWithRange:range]]scanHexInt:&blue];

return [UIColor colorWithRed:((float)red/255.0f) green:((float)green/255.0f) blue:((float)blue/255.0f) alpha:1.0f];
}
return [UIColor clearColor];
}