Is there a way one can represent a time only value in .NET without the date? For example, indicating the opening time of a shop?
TimeSpan indicates a range, whereas I only want to store a time value. Using DateTime to indicate this would result in new DateTime(1,1,1,8,30,0) which is not really desirable.
As others have said, you can use a DateTime and ignore the date, or use a TimeSpan. Personally I'm not keen on either of these solutions, as neither type really reflects the concept you're trying to represent - I regard the date/time types in .NET as somewhat on the sparse side which is one of the reasons I started Noda Time. In Noda Time, you can use the LocalTime type to represent a time of day.
Note that as of .NET 6, there are TimeOnly and DateOnly types which are roughly equivalent to Noda Time's LocalTime and LocalDate types.
One thing to consider: the time of day is not necessarily the length of time since midnight on the same day...
(As another aside, if you're also wanting to represent a closing time of a shop, you may find that you want to represent 24:00, i.e. the time at the end of the day. Most date/time APIs - including Noda Time - don't allow that to be represented as a time-of-day value.)
Duration in Noda Time, and a TimeSpan in .NET. –
Moquette Duration in Noda Time, or TimeSpan in the BCL. I'd probably encapsulate the "place in video + comment" as a type, and then have an array of that type. –
Moquette TimeOfDay property on the .NET DateTime object, so it's supposed to be used for that –
Nord TimeOfDay is a TimeSpan simply because there isn't a more suitable type in .NET. That doesn't mean it's a good use for it. What does a TimeSpan of 5 hours mean? It doesn't necessarily mean that 5 hours have passed since midnight - it means it's 5am. It's a broken representation, IMO. –
Moquette TimeSpan", it should be understandable that a reader might not think "Oh, maybe they talk about TimeOnly later on in this answer" :-) –
Prodigy TimeSpan, I have even less sympathy. (Even the first sentence says you can (with emphasis) rather than saying "use TimeSpan" - I think you've mischaracterized it significantly.) No-one should use Stack Overflow for "I only need to glance at an answer and half-read the first sentence without actually bothering to think." –
Moquette TimeOnly and land on this page looking for an answer that talks about how to use it, for example, I'm not going to bother reading past the first sentence or two of an answer before moving onto the next... because TimeOnly is now the best way to do it, so answers containing it should start with that (albeit with a warning that it's in .NET 6.0 only). And I know SO well. Imagine how a new/anonymous user would behave. –
Prodigy TimeOnly was not a net positive. I think moving it to the 2nd paragraph is a massive improvement and given that it's only for .NET 6.0 I think that's perfectly fine prominence for now. I was only saying that (in my humble opinion) adding it as an apparent afterthought (below two other options followed by your own custom library, of all things), was not ideal placement. –
Prodigy TimeOnly is the best way to do it, as I'd still recommend using Noda Time - chances are that if you need "time of day" you need other date/time-related concepts as well, and I still believe that Noda Time provides the best way of doing that. I suggest that this comment thread has really gone on long enough at this point though. –
Moquette You can use timespan
TimeSpan timeSpan = new TimeSpan(2, 14, 18);
Console.WriteLine(timeSpan.ToString()); // Displays "02:14:18".
[Edit]
Considering the other answers and the edit to the question, I would still use TimeSpan. No point in creating a new structure where an existing one from the framework suffice.
On these lines you would end up duplicating many native data types.
TimeSpan like this is somewhat ugly. It's the best that's available within the framework itself, but that's not the same as saying it's pleasant. –
Moquette new DateTime().TimeSpan and that new TimeSpan(hour, minute, second) both exists I find it pretty compelling that they fully intended TimeSpan to be used to start clock time and not just time deltas. –
Exist TimeSpan is used for two very different purposes - just like DateTime is used for values in UTC, local and unspecified time zones. Fundamentally, the date/time types in the framework have significant conceptual issues, IMO. –
Moquette DateTime and TimeSpan for things that seem to go against their name, but it depends how you view them. Personally I think it makes sense to think that a time of day is not a fixed point on its own. Without a date as a reference point, a time of day is just an offset into some arbitrary day. –
Porphyritic TimeSpan (such as adding two values) which simply don't make sense for time-of-day values. That sort of thing is why I think it's a bad idea to use TimeSpan to represent a time of day. –
Moquette Vectors in most physics and game libraries. Instead of declaring Points and Vectors to be separate, Vectors are used for both. Besides, sometimes a solution outside the core framework isn't ideal. Say for example if you are developing a library for external consumption, the more dependencies you use, the more dependencies you force on the consumers of your library. –
Porphyritic Point and Vector separately, and using a Vector when you mean a Point leads to confusing code. While I agree that adding dependencies isn't a great idea, I do think it's reasonable to point out that TimeSpan really isn't a brilliant fit for "time of day", and that your suggestion that it "this is exactly the solution to the proposed question" is ignoring that. Just because MS does it doesn't make it a good idea :) –
Moquette Point and Vector should be treated seperately and equally, my point was that many well known libraries choose to ignore this for simplicity. Feel free to disagree with MSDN but I'm going to stick with them this time. The OP and anyone else is free to choose whatever suits their situation, whether that is the standard library or an external library, but I know which side I'm sticking with. I can't really say much more without more information about the OP's situation. –
Porphyritic System.Data.SqlDbType.Time maps to System.TimeSpan. That's good enough for me. –
Inch As others have said, you can use a DateTime and ignore the date, or use a TimeSpan. Personally I'm not keen on either of these solutions, as neither type really reflects the concept you're trying to represent - I regard the date/time types in .NET as somewhat on the sparse side which is one of the reasons I started Noda Time. In Noda Time, you can use the LocalTime type to represent a time of day.
Note that as of .NET 6, there are TimeOnly and DateOnly types which are roughly equivalent to Noda Time's LocalTime and LocalDate types.
One thing to consider: the time of day is not necessarily the length of time since midnight on the same day...
(As another aside, if you're also wanting to represent a closing time of a shop, you may find that you want to represent 24:00, i.e. the time at the end of the day. Most date/time APIs - including Noda Time - don't allow that to be represented as a time-of-day value.)
Duration in Noda Time, and a TimeSpan in .NET. –
Moquette Duration in Noda Time, or TimeSpan in the BCL. I'd probably encapsulate the "place in video + comment" as a type, and then have an array of that type. –
Moquette TimeOfDay property on the .NET DateTime object, so it's supposed to be used for that –
Nord TimeOfDay is a TimeSpan simply because there isn't a more suitable type in .NET. That doesn't mean it's a good use for it. What does a TimeSpan of 5 hours mean? It doesn't necessarily mean that 5 hours have passed since midnight - it means it's 5am. It's a broken representation, IMO. –
Moquette TimeSpan", it should be understandable that a reader might not think "Oh, maybe they talk about TimeOnly later on in this answer" :-) –
Prodigy TimeSpan, I have even less sympathy. (Even the first sentence says you can (with emphasis) rather than saying "use TimeSpan" - I think you've mischaracterized it significantly.) No-one should use Stack Overflow for "I only need to glance at an answer and half-read the first sentence without actually bothering to think." –
Moquette TimeOnly and land on this page looking for an answer that talks about how to use it, for example, I'm not going to bother reading past the first sentence or two of an answer before moving onto the next... because TimeOnly is now the best way to do it, so answers containing it should start with that (albeit with a warning that it's in .NET 6.0 only). And I know SO well. Imagine how a new/anonymous user would behave. –
Prodigy TimeOnly was not a net positive. I think moving it to the 2nd paragraph is a massive improvement and given that it's only for .NET 6.0 I think that's perfectly fine prominence for now. I was only saying that (in my humble opinion) adding it as an apparent afterthought (below two other options followed by your own custom library, of all things), was not ideal placement. –
Prodigy TimeOnly is the best way to do it, as I'd still recommend using Noda Time - chances are that if you need "time of day" you need other date/time-related concepts as well, and I still believe that Noda Time provides the best way of doing that. I suggest that this comment thread has really gone on long enough at this point though. –
Moquette If that empty Date really bugs you, you can also to create a simpler Time structure:
// more work is required to make this even close to production ready
class Time
{
// TODO: don't forget to add validation
public int Hours { get; set; }
public int Minutes { get; set; }
public int Seconds { get; set; }
public override string ToString()
{
return String.Format(
"{0:00}:{1:00}:{2:00}",
this.Hours, this.Minutes, this.Seconds);
}
}
Or, why to bother: if you don't need to do any calculation with that information, just store it as String.
TimeSpan, which already handles this, and in a significantly better way. –
Yeld I say use a DateTime. If you don't need the date portion, just ignore it. If you need to display just the time to the user, output it formatted to the user like this:
DateTime.Now.ToString("t"); // outputs 10:00 PM
It seems like all the extra work of making a new class or even using a TimeSpan is unnecessary.
DateTime.Now.ToString("hh:mm:ss.fff"); Microseconds: DateTime.Now.ToString("hh:mm:ss.ffffff"); Nanoseconds (if DateTime even has that much resolution): DateTime.Now.ToString("hh:mm:ss.fffffffff"); As per MSDN –
Porphyritic I think Rubens' class is a good idea so thought to make an immutable sample of his Time class with basic validation.
class Time
{
public int Hours { get; private set; }
public int Minutes { get; private set; }
public int Seconds { get; private set; }
public Time(uint h, uint m, uint s)
{
if(h > 23 || m > 59 || s > 59)
{
throw new ArgumentException("Invalid time specified");
}
Hours = (int)h; Minutes = (int)m; Seconds = (int)s;
}
public Time(DateTime dt)
{
Hours = dt.Hour;
Minutes = dt.Minute;
Seconds = dt.Second;
}
public override string ToString()
{
return String.Format(
"{0:00}:{1:00}:{2:00}",
this.Hours, this.Minutes, this.Seconds);
}
}
In addition to Chibueze Opata:
class Time
{
public int Hours { get; private set; }
public int Minutes { get; private set; }
public int Seconds { get; private set; }
public Time(uint h, uint m, uint s)
{
if(h > 23 || m > 59 || s > 59)
{
throw new ArgumentException("Invalid time specified");
}
Hours = (int)h; Minutes = (int)m; Seconds = (int)s;
}
public Time(DateTime dt)
{
Hours = dt.Hour;
Minutes = dt.Minute;
Seconds = dt.Second;
}
public override string ToString()
{
return String.Format(
"{0:00}:{1:00}:{2:00}",
this.Hours, this.Minutes, this.Seconds);
}
public void AddHours(uint h)
{
this.Hours += (int)h;
}
public void AddMinutes(uint m)
{
this.Minutes += (int)m;
while(this.Minutes > 59)
this.Minutes -= 60;
this.AddHours(1);
}
public void AddSeconds(uint s)
{
this.Seconds += (int)s;
while(this.Seconds > 59)
this.Seconds -= 60;
this.AddMinutes(1);
}
}
Here's a full featured TimeOfDay class.
This is overkill for simple cases, but if you need more advanced functionality like I did, this may help.
It can handle the corner cases, some basic math, comparisons, interaction with DateTime, parsing, etc.
Below is the source code for the TimeOfDay class. You can see usage examples and learn more here:
This class uses DateTime for most of its internal calculations and comparisons so that we can leverage all of the knowledge already embedded in DateTime.
// Author: Steve Lautenschlager, CambiaResearch.com
// License: MIT
using System;
using System.Text.RegularExpressions;
namespace Cambia
{
public class TimeOfDay
{
private const int MINUTES_PER_DAY = 60 * 24;
private const int SECONDS_PER_DAY = SECONDS_PER_HOUR * 24;
private const int SECONDS_PER_HOUR = 3600;
private static Regex _TodRegex = new Regex(@"\d?\d:\d\d:\d\d|\d?\d:\d\d");
public TimeOfDay()
{
Init(0, 0, 0);
}
public TimeOfDay(int hour, int minute, int second = 0)
{
Init(hour, minute, second);
}
public TimeOfDay(int hhmmss)
{
Init(hhmmss);
}
public TimeOfDay(DateTime dt)
{
Init(dt);
}
public TimeOfDay(TimeOfDay td)
{
Init(td.Hour, td.Minute, td.Second);
}
public int HHMMSS
{
get
{
return Hour * 10000 + Minute * 100 + Second;
}
}
public int Hour { get; private set; }
public int Minute { get; private set; }
public int Second { get; private set; }
public double TotalDays
{
get
{
return TotalSeconds / (24d * SECONDS_PER_HOUR);
}
}
public double TotalHours
{
get
{
return TotalSeconds / (1d * SECONDS_PER_HOUR);
}
}
public double TotalMinutes
{
get
{
return TotalSeconds / 60d;
}
}
public int TotalSeconds
{
get
{
return Hour * 3600 + Minute * 60 + Second;
}
}
public bool Equals(TimeOfDay other)
{
if (other == null) { return false; }
return TotalSeconds == other.TotalSeconds;
}
public override bool Equals(object obj)
{
if (obj == null) { return false; }
TimeOfDay td = obj as TimeOfDay;
if (td == null) { return false; }
else { return Equals(td); }
}
public override int GetHashCode()
{
return TotalSeconds;
}
public DateTime ToDateTime(DateTime dt)
{
return new DateTime(dt.Year, dt.Month, dt.Day, Hour, Minute, Second);
}
public override string ToString()
{
return ToString("HH:mm:ss");
}
public string ToString(string format)
{
DateTime now = DateTime.Now;
DateTime dt = new DateTime(now.Year, now.Month, now.Day, Hour, Minute, Second);
return dt.ToString(format);
}
public TimeSpan ToTimeSpan()
{
return new TimeSpan(Hour, Minute, Second);
}
public DateTime ToToday()
{
var now = DateTime.Now;
return new DateTime(now.Year, now.Month, now.Day, Hour, Minute, Second);
}
#region -- Static --
public static TimeOfDay Midnight { get { return new TimeOfDay(0, 0, 0); } }
public static TimeOfDay Noon { get { return new TimeOfDay(12, 0, 0); } }
public static TimeOfDay operator -(TimeOfDay t1, TimeOfDay t2)
{
DateTime now = DateTime.Now;
DateTime dt1 = new DateTime(now.Year, now.Month, now.Day, t1.Hour, t1.Minute, t1.Second);
TimeSpan ts = new TimeSpan(t2.Hour, t2.Minute, t2.Second);
DateTime dt2 = dt1 - ts;
return new TimeOfDay(dt2);
}
public static bool operator !=(TimeOfDay t1, TimeOfDay t2)
{
if (ReferenceEquals(t1, t2)) { return true; }
else if (ReferenceEquals(t1, null)) { return true; }
else
{
return t1.TotalSeconds != t2.TotalSeconds;
}
}
public static bool operator !=(TimeOfDay t1, DateTime dt2)
{
if (ReferenceEquals(t1, null)) { return false; }
DateTime dt1 = new DateTime(dt2.Year, dt2.Month, dt2.Day, t1.Hour, t1.Minute, t1.Second);
return dt1 != dt2;
}
public static bool operator !=(DateTime dt1, TimeOfDay t2)
{
if (ReferenceEquals(t2, null)) { return false; }
DateTime dt2 = new DateTime(dt1.Year, dt1.Month, dt1.Day, t2.Hour, t2.Minute, t2.Second);
return dt1 != dt2;
}
public static TimeOfDay operator +(TimeOfDay t1, TimeOfDay t2)
{
DateTime now = DateTime.Now;
DateTime dt1 = new DateTime(now.Year, now.Month, now.Day, t1.Hour, t1.Minute, t1.Second);
TimeSpan ts = new TimeSpan(t2.Hour, t2.Minute, t2.Second);
DateTime dt2 = dt1 + ts;
return new TimeOfDay(dt2);
}
public static bool operator <(TimeOfDay t1, TimeOfDay t2)
{
if (ReferenceEquals(t1, t2)) { return true; }
else if (ReferenceEquals(t1, null)) { return true; }
else
{
return t1.TotalSeconds < t2.TotalSeconds;
}
}
public static bool operator <(TimeOfDay t1, DateTime dt2)
{
if (ReferenceEquals(t1, null)) { return false; }
DateTime dt1 = new DateTime(dt2.Year, dt2.Month, dt2.Day, t1.Hour, t1.Minute, t1.Second);
return dt1 < dt2;
}
public static bool operator <(DateTime dt1, TimeOfDay t2)
{
if (ReferenceEquals(t2, null)) { return false; }
DateTime dt2 = new DateTime(dt1.Year, dt1.Month, dt1.Day, t2.Hour, t2.Minute, t2.Second);
return dt1 < dt2;
}
public static bool operator <=(TimeOfDay t1, TimeOfDay t2)
{
if (ReferenceEquals(t1, t2)) { return true; }
else if (ReferenceEquals(t1, null)) { return true; }
else
{
if (t1 == t2) { return true; }
return t1.TotalSeconds <= t2.TotalSeconds;
}
}
public static bool operator <=(TimeOfDay t1, DateTime dt2)
{
if (ReferenceEquals(t1, null)) { return false; }
DateTime dt1 = new DateTime(dt2.Year, dt2.Month, dt2.Day, t1.Hour, t1.Minute, t1.Second);
return dt1 <= dt2;
}
public static bool operator <=(DateTime dt1, TimeOfDay t2)
{
if (ReferenceEquals(t2, null)) { return false; }
DateTime dt2 = new DateTime(dt1.Year, dt1.Month, dt1.Day, t2.Hour, t2.Minute, t2.Second);
return dt1 <= dt2;
}
public static bool operator ==(TimeOfDay t1, TimeOfDay t2)
{
if (ReferenceEquals(t1, t2)) { return true; }
else if (ReferenceEquals(t1, null)) { return true; }
else { return t1.Equals(t2); }
}
public static bool operator ==(TimeOfDay t1, DateTime dt2)
{
if (ReferenceEquals(t1, null)) { return false; }
DateTime dt1 = new DateTime(dt2.Year, dt2.Month, dt2.Day, t1.Hour, t1.Minute, t1.Second);
return dt1 == dt2;
}
public static bool operator ==(DateTime dt1, TimeOfDay t2)
{
if (ReferenceEquals(t2, null)) { return false; }
DateTime dt2 = new DateTime(dt1.Year, dt1.Month, dt1.Day, t2.Hour, t2.Minute, t2.Second);
return dt1 == dt2;
}
public static bool operator >(TimeOfDay t1, TimeOfDay t2)
{
if (ReferenceEquals(t1, t2)) { return true; }
else if (ReferenceEquals(t1, null)) { return true; }
else
{
return t1.TotalSeconds > t2.TotalSeconds;
}
}
public static bool operator >(TimeOfDay t1, DateTime dt2)
{
if (ReferenceEquals(t1, null)) { return false; }
DateTime dt1 = new DateTime(dt2.Year, dt2.Month, dt2.Day, t1.Hour, t1.Minute, t1.Second);
return dt1 > dt2;
}
public static bool operator >(DateTime dt1, TimeOfDay t2)
{
if (ReferenceEquals(t2, null)) { return false; }
DateTime dt2 = new DateTime(dt1.Year, dt1.Month, dt1.Day, t2.Hour, t2.Minute, t2.Second);
return dt1 > dt2;
}
public static bool operator >=(TimeOfDay t1, TimeOfDay t2)
{
if (ReferenceEquals(t1, t2)) { return true; }
else if (ReferenceEquals(t1, null)) { return true; }
else
{
return t1.TotalSeconds >= t2.TotalSeconds;
}
}
public static bool operator >=(TimeOfDay t1, DateTime dt2)
{
if (ReferenceEquals(t1, null)) { return false; }
DateTime dt1 = new DateTime(dt2.Year, dt2.Month, dt2.Day, t1.Hour, t1.Minute, t1.Second);
return dt1 >= dt2;
}
public static bool operator >=(DateTime dt1, TimeOfDay t2)
{
if (ReferenceEquals(t2, null)) { return false; }
DateTime dt2 = new DateTime(dt1.Year, dt1.Month, dt1.Day, t2.Hour, t2.Minute, t2.Second);
return dt1 >= dt2;
}
/// <summary>
/// Input examples:
/// 14:21:17 (2pm 21min 17sec)
/// 02:15 (2am 15min 0sec)
/// 2:15 (2am 15min 0sec)
/// 2/1/2017 14:21 (2pm 21min 0sec)
/// TimeOfDay=15:13:12 (3pm 13min 12sec)
/// </summary>
public static TimeOfDay Parse(string s)
{
// We will parse any section of the text that matches this
// pattern: dd:dd or dd:dd:dd where the first doublet can
// be one or two digits for the hour. But minute and second
// must be two digits.
Match m = _TodRegex.Match(s);
string text = m.Value;
string[] fields = text.Split(':');
if (fields.Length < 2) { throw new ArgumentException("No valid time of day pattern found in input text"); }
int hour = Convert.ToInt32(fields[0]);
int min = Convert.ToInt32(fields[1]);
int sec = fields.Length > 2 ? Convert.ToInt32(fields[2]) : 0;
return new TimeOfDay(hour, min, sec);
}
#endregion
private void Init(int hour, int minute, int second)
{
if (hour < 0 || hour > 23) { throw new ArgumentException("Invalid hour, must be from 0 to 23."); }
if (minute < 0 || minute > 59) { throw new ArgumentException("Invalid minute, must be from 0 to 59."); }
if (second < 0 || second > 59) { throw new ArgumentException("Invalid second, must be from 0 to 59."); }
Hour = hour;
Minute = minute;
Second = second;
}
private void Init(int hhmmss)
{
int hour = hhmmss / 10000;
int min = (hhmmss - hour * 10000) / 100;
int sec = (hhmmss - hour * 10000 - min * 100);
Init(hour, min, sec);
}
private void Init(DateTime dt)
{
Init(dt.Hour, dt.Minute, dt.Second);
}
}
}
A System.TimeOfDay type was recently approved for an upcoming release of .NET 6.
See https://github.com/dotnet/runtime/issues/49036
When complete, this will be the preferred way of representing time of day values that are not associated with any particular date or time zone.
System.TimeSpan will still be the recommended way to represent elapsed time values.
If you don't want to use a DateTime or TimeSpan, and just want to store the time of day, you could just store the seconds since midnight in an Int32, or (if you don't even want seconds) the minutes since midnight would fit into an Int16. It would be trivial to write the few methods required to access the Hour, Minute and Second from such a value.
The only reason I can think of to avoid DateTime/TimeSpan would be if the size of the structure is critical.
(Of course, if you use a simple scheme like the above wrapped in a class, then it would also be trivial to replace the storage with a TimeSpan in future if you suddenly realise that would give you an advantage)
You can simply use validation constraint.
[DataType(DataType.Time)]
public DateTime OpeningTime { get; set; }
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