根据日期判断星期几

  根据日期判断星期几

  [_comps setDay:23];

    [_comps setMonth:3];

    [_comps setYear:2014];

    NSCalendar *gregorian = [[NSCalendar alloc]
                             initWithCalendarIdentifier:NSGregorianCalendar];

    NSDate *_date = [gregorian dateFromComponents:_comps];

    NSDateComponents *weekdayComponents =

    [gregorian components:NSWeekdayCalendarUnit fromDate:_date];

    int _weekday = [weekdayComponents weekday];
    NSLog(@"_weekday::%d",_weekday);

2、

+ (NSInteger)acquireWeekDayFromDate:(NSDate*)date {

    NSCalendar* calendar = [NSCalendar currentCalendar];

    unsigned unitFlags = NSCalendarUnitWeekday;

    NSDateComponents* comps = [calendar components:unitFlags fromDate:date];

    return [comps weekday];

}

//在这里需要注意的是：星期日是数字1，星期一时数字2，以此类推