我的约会伙伴是这样的“ 2019-12-03T05：58：11.317Z”。我想将相同的日期元素分组。我可以基于日期创建UITableView节。这是数组，我有三个不同的日期，所以我想创建3个部分。这里的问题是 newArrayList ，不保存所有元素。
NSMutableArray * arrayList;
NSMutableArray *newArrayList;
//This is my date array
arrayList = [[NSMutableArray alloc] initWithObjects:@“2019-12-03T05:58:11.317Z”, @“2019-12-03T05:58:10.317Z”, @“2019-12-03T05:58:01.317Z”, @“2019-12-03T05:55:12.448Z”, @“2019-12-03T05:48:11.317Z”, @“2019-12-03T05:28:11.317Z”, @“2019-12-03T05:11:24.004Z”, @“2019-12-03T05:28:11.317Z”, @“2019-12-03T05:55:12.965Z”, @“2019-12-02T15:09:35.408Z”, @“2019-12-02T15:09:38.187Z”, @“2019-12-02T15:43:02.118Z”, @“2019-12-02T15:44:09.344Z”, @“2019-12-02T17:07:55.038Z”, @“2019-12-02T16:42:16.649Z”, @“2019-12-01T16:42:16.649Z”, nil];
newArrayList = [[NSMutableArray alloc]init];//Here I want to same date elements
NSDate *fromDate;
NSMutableArray *tempArray = [[NSMutableArray alloc] init];
for (int i=0; i<arrayList.count; i++) {
NSDate *dt1 = fromDate;
NSDate *dt2 = [self getLocalDateTimeFromUTC2:[arrayList objectAtIndex:i]];
if (i != 0) {
if ([self isSameDay:dt1 otherDay:dt2] == YES) {
[tempArray addObject:t];
} else {
[newArrayList addObject:tempArray];
// [tempArray removeAllObjects];
}
}
fromDate = dt2;
}
//To get required date formate
-(NSDate *)getLocalDateTimeFromUTC2:(NSString *)strDate
{
// create dateFormatter with UTC time format
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.SSSZZZZ"]; //@"yyyy-MM-dd'T'HH:mm:ss.SSSZZZZ"
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
// NSLog(@"%@", t.dateAndTime); //2019-12-02T15:09:38.187Z
NSDate *date = [dateFormatter dateFromString:strDate]; // create date from string
// change to a readable time format and change to local time zone
[dateFormatter setDateFormat:@"dd-MM-yyyy"];
[dateFormatter setTimeZone:[NSTimeZone localTimeZone]];
NSString *timestamp = [dateFormatter stringFromDate:date];
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:@"dd-MM-yyyy"];
[dateFormat setTimeZone:[NSTimeZone localTimeZone]];
NSDate *date2 = [dateFormat dateFromString:timestamp];
// NSLog(@"%@", date2);
return date2;
}
//To compare two dates
- (BOOL)isSameDay:(NSDate*)date1 otherDay:(NSDate*)date2 {
NSCalendar* calendar = [NSCalendar currentCalendar];
unsigned unitFlags = NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay;
NSDateComponents* comp1 = [calendar components:unitFlags fromDate:date1];
NSDateComponents* comp2 = [calendar components:unitFlags fromDate:date2];
return [comp1 day] == [comp2 day] && [comp1 month] == [comp2 month] && [comp1 year] == [comp2 year];
}
答案 0 :(得分：1)
尝试一下：
NSMutableDictionary *dictByDate = [NSMutableDictionary new];
NSMutableArray *newArr = [NSMutableArray new] ;
for(NSString *strDate in arrayList)
{
// convert date to proper formate (if needed)
NSDateFormatter *format = [[NSDateFormatter alloc] init];
[format setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.SSSZZZZ"];
NSDate *dateNew = [format dateFromString:strDate];
[format setDateFormat:@"MMMM-dd-yyyy"];
NSString *finalDateString = [format stringFromDate:dateNew];
NSLog(@"%@",finalDateString) ;
NSMutableArray *arrWithSameDate = dictByDate[finalDateString];
if(! arrWithSameDate)
{
arrWithSameDate = [NSMutableArray new];
dictByDate[finalDateString] = arrWithSameDate;
}
[arrWithSameDate addObject: strDate];
}
[newArr addObjectsFromArray:[dictByDate allValues]] ;
NSLog(@"group data: %@", newArr);
答案 1 :(得分：1)
我正在迅速进行中，希望您能在obj-c中进行管理
假设您有以下数据
let arrDates = [ "2019-12-03T05:58:11.317Z ", "2019-12-03T05:58:10.317Z ", "2019-12-03T05:58:01.317Z ", "2019-12-03T05:55:12.448Z ", "2019-12-03T05:48:11.317Z ", "2019-12-03T05:28:11.317Z ", "2019-12-03T05:11:24.004Z ", "2019-12-03T05:28:11.317Z ", "2019-12-03T05:55:12.965Z ", "2019-12-02T15:09:35.408Z ", "2019-12-02T15:09:38.187Z ", "2019-12-02T15:43:02.118Z ", "2019-12-02T15:44:09.344Z ", "2019-12-02T17:07:55.038Z ", "2019-12-02T16:42:16.649Z ", "2019-12-01T16:42:16.649Z "]
设定日期组
let dictGroupDate = Dictionary(grouping: arrDates) { (strdate) -> String in
let df = DateFormatter()
df.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZZZZ"
let date = df.date(from: strdate)
df.dateFormat = "yyyy-MM-dd"
return df.string(from: date!)
}
获取所有节日期并对它们进行排序
let arrDateKey = Array(dictGroupDate.keys).sorted { (strdate1, strdate2) -> Bool in
let df = DateFormatter()
df.dateFormat = "yyyy-MM-dd"
let date1 = df.date(from: strdate1)
let date2 = df.date(from: strdate2)
return date1!.compare(date2!) == .orderedAscending
}
为每个日期排序时间并创建新字典
var newGroupedDates = [String : [String]]()
for strKey in arrDateKey {
let sortedTime = dictGroupDate[strKey]?.sorted(by: { (strdate1, strdate2) -> Bool in
let df = DateFormatter()
df.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSZZZZ"
let date1 = df.date(from: strdate1)
let date2 = df.date(from: strdate2)
return date1!.compare(date2!) == .orderedAscending
})
newGroupedDates[strKey] = sortedTime!
}
在UITABLEVIEW中显示数据
// NumberOfSections
arrDateKey.count
//NumberOfRows
let key = arrDateKey[indexPath.section]
newGroupedDates[key]?.count
// CellForRow
// To get correct date and Time
let key = arrDateKey[indexPath.section]
let item = newGroupedDates[key]![indexPath.row]
// Now item is the date string, and do whatever you wanted to do.
输出
最终newGroupedDates
["2019-12-03": ["2019-12-03T05:11:24.004Z ", "2019-12-03T05:28:11.317Z ", "2019-12-03T05:28:11.317Z ", "2019-12-03T05:48:11.317Z ", "2019-12-03T05:55:12.448Z ", "2019-12-03T05:55:12.965Z ", "2019-12-03T05:58:01.317Z ", "2019-12-03T05:58:10.317Z ", "2019-12-03T05:58:11.317Z "], "2019-12-02": ["2019-12-02T15:09:35.408Z ", "2019-12-02T15:09:38.187Z ", "2019-12-02T15:43:02.118Z ", "2019-12-02T15:44:09.344Z ", "2019-12-02T16:42:16.649Z ", "2019-12-02T17:07:55.038Z "], "2019-12-01": ["2019-12-01T16:42:16.649Z "]]
以防万一我错过了一些东西然后发表评论。
答案 2 :(得分：0)
一些注意事项： 1）出于多种原因，请勿将日期保留为字符串： a）日期使用较少的内存 b）您可以使用但在考虑了时区和跳跃的功能中进行比较和排序。
2）不要在每个地方都创建格式化程序（即，将therm放在外面） 按照Apple的要求：