自學iOS-獲取當前時間

NSDate *  senddate=[NSDate date];  

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

[dateformatter setDateFormat:@"YYYYMMdd"];  

NSString *  locationString=[dateformatter stringFromDate:senddate];    

NSLog(@"locationString:%@",locationString);

 [dateformatter release]; //這個有問題，顯示日期不對

 

關大叔的寫法

01    //獲取當前時間
02    NSDate *now = [NSDate date];
03    NSLog(@」now date is: %@」, now);
04
05    NSCalendar *calendar = [NSCalendar currentCalendar];
06    NSUInteger unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
07    NSDateComponents *dateComponent = [calendar components:unitFlags fromDate:now];
08     
09    int year = [dateComponent year];
10    int month = [dateComponent month];
11    int day = [dateComponent day];
12    int hour = [dateComponent hour];
13    int minute = [dateComponent minute];
14    int second = [dateComponent second];
15
16    NSLog(@」year is: %d」, year);
17    NSLog(@」month is: %d」, month);
18    NSLog(@」day is: %d」, day);
19    NSLog(@」hour is: %d」, hour);
20    NSLog(@」minute is: %d」, minute);
21    NSLog(@」second is: %d」, second);

 

獲取星期幾（好用的）能夠獲取：年、月、日、星期幾

　　 NSDate *datet = [NSDate date];//如今時間
    NSArray *weekdays = [NSArray arrayWithObjects: [NSNull null], @"Sunday", @"週一", @"週二", @"週三", @"週四", @"週五", @"週六", nil];
    
    NSCalendar *calendars = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
    
    NSTimeZone *timeZone = [[NSTimeZone alloc] initWithName:@"Asia/Shanghai"];
    
    [calendars setTimeZone: timeZone];
    
    NSCalendarUnit calendarUnit = NSCalendarUnitWeekday;
    
    NSDateComponents *theComponents = [calendars components:calendarUnit fromDate:datet];
    
    NSInteger unitFlagss = NSCalendarUnitYear |
    NSCalendarUnitMonth |
    NSCalendarUnitDay |
    NSCalendarUnitWeekday |
    NSCalendarUnitHour |
    NSCalendarUnitMinute |
    NSCalendarUnitSecond;
    
    theComponents = [calendars components:unitFlagss fromDate:datet];
    int week = [theComponents weekday];
    int year=[theComponents year];
    int month = [theComponents month];
    int day = [theComponents day];
    
    NSLog(@"%d年%d月",year,month);
    NSLog(@"%d",day);
    
    NSLog(@"xingqi%@",[weekdays objectAtIndex:theComponents.weekday]);