iOS日历时间相关整理

1.当前月有多少天

NSCalendar *calendar = [NSCalendar currentCalendar];

NSRange range = [calendar rangeOfUnit:NSDayCalendarUnit inUnit:NSMonthCalendarUnit forDate:[NSDate date]];

NSUInteger numberOfDaysInMonth = range.length;

NSLog(@"%lu", (unsigned long)numberOfDaysInMonth);

2.获取每月的第一天和最后一天

- (NSString *)getMonthBeginAndEndWith:(NSString *)dateStr{

    NSDateFormatter *format=[[NSDateFormatter alloc] init];

    [format setDateFormat:@"yyyy-MM"];

    NSDate *newDate=[format dateFromString:dateStr];

    double interval = 0;

    NSDate *beginDate = nil;

    NSDate *endDate = nil;

    NSCalendar *calendar = [NSCalendar currentCalendar];

    [calendar setFirstWeekday:2];//设定周一为周首日

    BOOL ok = [calendar rangeOfUnit:NSMonthCalendarUnit startDate:&beginDate interval:&interval forDate:newDate];

    //分别修改为 NSDayCalendarUnit NSWeekCalendarUnit NSYearCalendarUnit

    if (ok) {

        endDate = [beginDate dateByAddingTimeInterval:interval-1];

    }else {

        return @"";

    }

    NSDateFormatter *myDateFormatter = [[NSDateFormatter alloc] init];

    [myDateFormatter setDateFormat:@"YYYY年MM月dd日"];

    NSString *beginString = [myDateFormatter stringFromDate:beginDate];

    NSString *endString = [myDateFormatter stringFromDate:endDate];

    NSString *s = [NSString stringWithFormat:@"%@-%@",beginString,endString];

    return s;

}

//调用格式（yyyy-MM）

NSString *dateStr = [self getMonthBeginAndEndWith:@"2019-10"];

3.月份是星期几

- (NSDictionary *)weekdayStringWithDate:(NSDate *)date {

    //获取星期几

    NSDateComponents *componets = [[NSCalendar autoupdatingCurrentCalendar] components:NSCalendarUnitWeekday fromDate:date];

    NSInteger weekday = [componets weekday];//1代表星期日，2代表星期一，后面依次

    NSArray *weekArray = @[@{@"date":@"星期日",@"index":@"0"},@{@"date":@"星期一",@"index":@"1"},@{@"date":@"星期二",@"index":@"2"},@{@"date":@"星期三",@"index":@"3"},@{@"date":@"星期四",@"index":@"4"},@{@"date":@"星期五",@"index":@"5"},@{@"date":@"星期六",@"index":@"6"}];

    NSDictionary *weekDic = weekArray[weekday-1];

    return weekDic;

}

//传入NSDate类型

NSDate *date1 = [self getDate:dateStringArray[0]];

NSDate *date2 = [self getDate:dateStringArray[1]];

NSString *weekStr = [self weekdayStringWithDate:date1][@"date"];

4.时间字符串转NSDate

//时间字符串转Date

- (NSDate *)getDate:(NSString *)dataStr{

    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];

    [dateFormatter setDateFormat:@"yyyy年MM月dd日"];

    NSDate *date = [dateFormatter dateFromString:dataStr];

    return date;

}