I have run into an issue. I'm obtaining a date time string from the database and and some of these date time strings does not contain time. But as for the new requirement every date time string should contain the time like so,
1)1980/10/11 12:00:01
2)2010/APRIL/02 17:10:00
3)10/02/10 03:30:34
Date can be in any format followed by the time in 24hr notation.
I tried to detect the existence of time via the following code,
string timestamp_string = "2013/04/08 17:30";
DateTime timestamp = Convert.ToDateTime(timestamp_string);
string time ="";
if (timestamp_string.Length > 10)
{
time = timestamp.ToString("hh:mm");
}
else {
time = "Time not registered";
}
MessageBox.Show(time);
But this only works for the No 1) type timestamps. May I please know how to achieve this task on how to detect if the time element exist in this date time string. Thank you very much :)
POSSIBLE MATCH
How to validate if a "date and time" string only has a time?
INFO the three answers provided by Arun Selva Kumar,Guru Kara,Patipol Paripoonnanonda are all correct and checks for the time and serves my purpose. But I select Guru Karas answer solely on ease of use and for the explanation he has given. Thank you very much :) very much appreciated all of you :)
The date time components TimeOfDay is what you need.
MSDN says "Unlike the Date property, which returns a DateTime value that represents a date without its time component, the TimeOfDay property returns a TimeSpan value that represents a DateTime value's time component."
Here is an example with consideration of all your scenarios.
Since you are sure of the format you can use DateTime.Parse else please use DateTime.TryParse
var dateTime1 = System.DateTime.Parse("1980/10/11 12:00:00");
var dateTime2 = System.DateTime.Parse("2010/APRIL/02 17:10:00");
var dateTime3 = System.DateTime.Parse("10/02/10 03:30:34");
var dateTime4 = System.DateTime.Parse("02/20/10");
if (dateTime1.TimeOfDay.TotalSeconds == 0) {
Console.WriteLine("1980/10/11 12:00:00 - does not have Time");
} else {
Console.WriteLine("1980/10/11 12:00:00 - has Time");
}
if (dateTime2.TimeOfDay.TotalSeconds == 0) {
Console.WriteLine("2010/APRIL/02 17:10:00 - does not have Time");
} else {
Console.WriteLine("2010/APRIL/02 17:10:00 - Has Time");
}
if (dateTime3.TimeOfDay.TotalSeconds == 0) {
Console.WriteLine("10/02/10 03:30:34 - does not have Time");
} else {
Console.WriteLine("10/02/10 03:30:34 - Has Time");
}
if (dateTime4.TimeOfDay.TotalSeconds == 0) {
Console.WriteLine("02/20/10 - does not have Time");
} else {
Console.WriteLine("02/20/10 - Has Time");
}
Try this,
DateTime myDate;
if (DateTime.TryParseExact(inputString, "dd-MM-yyyy hh:mm:ss",
CultureInfo.InvariantCulture, DateTimeStyles.None, out myDate))
{
//String has Date and Time
}
else
{
//String has only Date Portion
}
You can try using other format specifiers as listed here, http://msdn.microsoft.com/en-us/library/8kb3ddd4.aspx
Combining the answers of Guru Kara and Patipol Paripoonnanonda with the .net globalisation API results in:
bool HasExplicitTime(DateTime parsedTimestamp, string str_timestamp)
{
string[] dateTimeSeparators = { "T", " ", "#" };
string[] timeSeparators = {
CultureInfo.CurrentUICulture.DateTimeFormat.TimeSeparator,
CultureInfo.CurrentCulture.DateTimeFormat.TimeSeparator,
":"};
if (parsedTimestamp.TimeOfDay.TotalSeconds != 0)
return true;
string[] dateOrTimeParts = str_timestamp.Split(
dateTimeSeparators,
StringSplitOptions.RemoveEmptyEntries);
bool hasTimePart = dateOrTimeParts.Any(part =>
part.Split(
timeSeparators,
StringSplitOptions.RemoveEmptyEntries).Length > 1);
return hasTimePart;
}
This approach:
detects explicit midnight times (e.g. "2015-02-26T00:00");
only searches the string when TimeOfDay indicates midnight or no explicit time; and
finds explicit midnight times in local format and any non midnight time in any format that .net can parse.
Limitations:
explicit midnight times in non culture local format are not detected;
explicit midnight times with less than two parts are not detected; and
less simple and elegant than the approaches of Guru Kara and Patipol Paripoonnanonda.
Here's what I'm going with for now. It may not be perfect, but likely better than considering any 12am datetime as not having a time. The premise is that if I tack a full time specification on the end it will parse if it's just a date but fail if it already has a time component.
I had to make the assumption that there's not some valid, date/time that has 7 non-white-space characters or less. It appears that "1980/10" parses, but not "1980/10 01:01:01.001".
I've included various test cases. Feel free to add your own and let me know if they fail.
public static bool IsValidDateTime(this string dateString, bool requireTime = false)
{
DateTime outDate;
if(!DateTime.TryParse(dateString, out outDate)) return false;
if (!requireTime) return true;
else
{
return Regex.Replace(dateString, #"\s", "").Length > 7
&& !DateTime.TryParse(dateString + " 01:01:01.001", out outDate);
}
}
public void DateTest()
{
var withTimes = new[]{
"1980/10/11 01:01:01.001",
"02/01/1980 01:01:01.001",
"1980-01-01 01:01:01.001",
"1980/10/11 00:00",
"1980/10/11 1pm",
"1980-01-01 00:00:00"};
//Make sure our ones with time pass both tests
foreach(var date in withTimes){
Assert.IsTrue(date.IsValidDateTime(), String.Format("date: {0} isn't valid.", date));
Assert.IsTrue(date.IsValidDateTime(true), String.Format("date: {0} does have time.", date));
}
var withoutTimes = new[]{
"1980/10/11",
"1980/10",
"1980/10 ",
"10/1980",
"1980 01",
"1980/10/11 ",
"02/01/1980",
"1980-01-01"};
//Make sure our ones without time pass the first and fail the second
foreach (var date in withoutTimes)
{
Assert.IsTrue(date.IsValidDateTime(), String.Format("date: {0} isn't valid.", date));
Assert.IsFalse(date.IsValidDateTime(true), String.Format("date: {0} doesn't have time.", date) );
}
var bogusTimes = new[]{
"1980",
"1980 01:01",
"80 01:01",
"1980T01",
"80T01:01",
"1980-01-01T01",
};
//Make sure our ones without time pass the first and fail the second
foreach (var date in bogusTimes)
{
DateTime parsedDate;
DateTime.TryParse(date, out parsedDate);
Assert.IsFalse(date.IsValidDateTime(), String.Format("date: {0} is valid. {1}", date, parsedDate));
Assert.IsFalse(date.IsValidDateTime(true), String.Format("date: {0} is valid. {1}", date, parsedDate));
}
}
Would this work for your use case:
bool noTime = _datetimevalue.TimeOfDay.Ticks == 0;
If no time component exists in the DateTime instance, Ticks will be 0.
Date and time are always separated by a space bar. The easiest way would be:
if (timestamp_string.Split(' ').Length == 2)
{
// timestamp_string has both date and time
}
else
{
// timestamp_string only has the date
}
This code assumes the date always exists.
If you want take it further (in case the date does not exist), you can do:
if (timestamp_string.Split(' ')
.Select(item => item.Split(':').Length > 1)
.Any(item => item))
{
// this would work for any string format that contains date, for example:
// 2012/APRIL/03 12:00:05 -> this would work
// 2013/04/05 09:00:01 -> this would work
// 08:50:45 2013/01/01 -> this would also work
// 08:50:50 -> this would also work
}
else
{
// no date in the timestamp_string at all
}
Hope this helps!
Related
string today = "#datetime";
if (today == DateTime.Now.ToString("dd/MM/yyyy"))
{
Application.Run(new ClipboardNotification.NotificationForm());
}
else
{
Application.Run(new ClipboardNotification2.NotificationForm());
}
so apparently in this code above there is a method would run within only 1 IF statement after todays daily date has past, so I wanted to make it run after 2 days instead of 1 day so what should I put their?
any help would be appreciated
Compare the Dates with DateTime or TimeSpan which will be easier. Don't use strings for dates as they can't be compared (eg 11/23/2021 vs 23/11/2021). Try like this I hope its helps:
var date = new DateTime(2021,11,23);
if(date > DateTime.Today.AddDays(2))
{
// do stuff
}
const int intervalDays = 2; // desired interval
string dateString = "30/11/2021";
DateTime convertedDate = DateTime.ParseExact(dateString, "dd/MM/yyyy", CultureInfo.InvariantCulture);
TimeSpan gap = DateTime.Now - convertedDate;
if (Math.Abs(gap.Days) < intervalDays)
{
Console.WriteLine("logic for less than 2 days");
//Application.Run(new ClipboardNotification.NotificationForm());
}
else
{
Console.WriteLine("logic for greater than or equal to 2 days");
//Application.Run(new ClipboardNotification2.NotificationForm());
}
check if this works for you.
I have a property in my clas:
public string Starttime
This is a input value from the client side. Now I want this value to compare with the time of the computer.
Pseudo code:
if(inputvalue startime = time on the computer){
//do something
}
else{
thread.sleep(100)
}
The syntax of the time must not be Datetime but only the time like 13:00, 13:00, 14:57 etc.
Which datatype is best to achieve this requirement?
You can consider using a TimeSpan to keep just the hours and minutes and you'll be good.
Alternatively, you can get the entire date and only compare the TimeOfDay property:
var endTime = DateTime.Now;
if(startTime.Hour == endTime.Hour && startTime.Minute == startTime.Minute)
{
// Do what you do when they are equal...
}
else
{
// They are not equal. Which is more likely.
}
Also, I'd advise using a DateTime object as opposed to a string for that.
Update
Another way to cater for the slight differences if you have a tolerance is as follows:
var endTime = DateTime.Now; // Here I am assuming a tolerance of 2 seconds.
if(endTime.Subtract(startTime).Seconds <= 2)
{
// Basically the same.
}
else
{
// Different as far as we are concerned.
}
You can use the TimeSpan type to represent hours and minutes. It has a Parse method that will take your input string and convert it to a TimeSpan. Then you can compare the time with the current time, using DateTime.Now.TimeOfDay:
static void Main(string[] args)
{
var clientInput = "14:57";
var startTime = TimeSpan.Parse(clientInput);
var currentTime = DateTime.Now.TimeOfDay;
Console.WriteLine("The start time is: {0}", startTime.ToString("hh\\:mm"));
Console.WriteLine("The current time is: {0}", currentTime.ToString("hh\\:mm"));
var difference = currentTime.Subtract(startTime);
if ((int)difference.TotalMinutes == 0)
{
Console.WriteLine("It's time to start!");
}
else if ((int)difference.TotalMinutes > 0)
{
Console.WriteLine("We should have started {0} minutes ago!",
(int)difference.TotalMinutes);
}
else
{
Console.WriteLine("We will start in: {0} hours and {1} minutes.",
-difference.Hours, -difference.Minutes);
}
Console.Write("\nDone!\nPress any key to exit...");
Console.ReadKey();
}
Output
You can use TimeSpan as the datatype. Here is the MSDN reference with all the methods and properties that you should have access to:
https://msdn.microsoft.com/en-us/library/system.timespan(v=vs.110).aspx
https://msdn.microsoft.com/en-us/library/system.timespan(v=vs.90).aspx
Hope this can help you out.
I am working on a reminder application. The applications stores the reminder Date, Time and DateLastShown (in different fields) in the database and pulls them out to performs checks.
All dates are in "d/MM/yyyy" format. My problem is that when i pull the dates from the DB and try to store back into DateTime format they are still being shown in "M/d/yyyy" format which is not how the app needs to be.
I essentially need to pull the values from the DB do some checks to determine if it's time to show the reminder and do so. It seems rather straight forward, maybe i am making some small error.
Below is my code with comments.
Any help really appreciated.
public void CheckReminders()
{
IQueryable<Reminder> reminders;
DateTime reminderDate;
DateTime reminderTime;
DateTime reminderLastShown;
DateTime todayDate;
DateTime timeNow;
while (true)
{
try
{
db = new StudioManagementEntities();
reminders = from r in db.Reminders
select r;
foreach (Reminder r in reminders)
{
if (r.Enabled == 1)
{
if (r.Recurring == 1)
{
// This is the code i was using before when the date was in "M/d/yyyy" format
// which seems to be default.
reminderTime = DateTime.Parse(r.Time);
timeNow = DateTime.Parse(DateTime.Now.ToLongTimeString());
if (r.DateLastShown != DateTime.Today.ToShortDateString() && timeNow >= reminderTime)
{
FrmReminder frmReminder = new FrmReminder(r.Id, true);
frmReminder.ShowDialog();
r.DateLastShown = DateTime.Today.ToShortDateString();
}
}
else
{
// Now i need to pass in "d/M/yyyy" format but the
// code seems to return in "M/d/yyyy" format.
reminderDate = DateTime.ParseExact(r.Date, "d/MM/yyyy", null);
// Even this returns in wrong format
reminderDate = DateTime.ParseExact("24/01/2013", "d/MM/yyyy", null);
// Have tried with CultureInfo.InvariantCulture too.
MessageBox.Show(reminderDate.ToString());
return;
if (
r.DateLastShown != DateTime.Today.Date.ToShortDateString() //&&
//r.Date == DateTime.ParseExact(DateTime.Today, "d/MM/yyyy", CultureInfo.InvariantCulture).ToString() //&&
//now.TimeOfDay.TotalSeconds >= reminderTime.TimeOfDay.TotalSeconds
)
{
FrmReminder frmReminder = new FrmReminder(r.Id, true);
frmReminder.ShowDialog();
r.DateLastShown = DateTime.Today.ToShortDateString();
}
}
}
}
db.SaveChanges();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
// Check every minute
Thread.Sleep(60000);
}
}
And the DB table.
If the parsing into the date object is not erroring out, you are just having a problem with your output when you call .ToString().
From the docs:
The ToString method returns the string representation of the date and
time in the calendar used by the current culture.
If you need something other than the user's current culture settings, you can specify that using a format string in the overloaded ToString() method:
var reminderDate = DateTime.ParseExact("24/01/2013", "d/MM/yyyy", null);
MessageBox.Show(reminderDate.ToString("d/MM/yyyy"));
Also, as others have stated in comments, if possible you should be using the date data type in your database instead of storing the values as strings.
I'm attempting to parse user input with Noda Time.
Input:
Date in the form of YYYY-MM-DD
Hour
Minute
tz database time zone name (returned from Google's Time Zone API)
I need to convert this data to UTC and to other time zones, also based on a tz database time zone name.
Currently I'm trying to make sense of the LocalDateTime and ZonedDateTime differences, but perhaps someone is able to show how to do this before I'd (hopefully) figure this out.
Your answer is pretty close to what I'd do - but if you have the date, hour and minute in separate strings, I'd use:
var zoneProvider = DateTimeZoneProviders.Tzdb;
var sourceZone = zoneProvider.GetZoneOrNull("Europe/Brussels");
var targetZone = zoneProvider.GetZoneOrNull("Australia/Melbourne");
if (sourceZone == null || targetZone == null)
{
Console.WriteLine("Time zone not found");
return;
}
var dateParseResult = LocalDatePattern.IsoPattern.Parse(date);
int hourValue, minuteValue;
if (!dateParseResult.Success ||
!int.TryParse(hour, out hourValue) ||
!int.TryParse(minute, out minuteValue))
{
Console.WriteLine("Parsing failed");
return;
}
var localDateTime = dateParseResult.Value + new LocalTime(hour, minute);
var zonedDateTime = localDateTime.InZoneStrictly(sourceZone);
Console.WriteLine(zonedDateTime.ToInstant());
Console.WriteLine(zonedDateTime);
Console.WriteLine(zonedDateTime.WithZone(targetZone));
The only significant difference here is the parsing - I wouldn't stick all the bits together; I'd just parse the strings separately. (I also prefer "early outs" for failures :)
You should note the meaning of InZoneStrictly though - do you definitely want to fail if the input local date/time is ambiguous?
http://msmvps.com/blogs/jon_skeet/archive/2012/02.aspx has great information, and while it's slightly outdated it's easy to find the relevant method names in the official documentation.
Below is some demonstration code.
string date = "2013-01-22";
string hour = "13";
string minute = "15";
var result = LocalDateTimePattern.ExtendedIsoPattern.Parse(date + "T" + hour + ":" + minute + ":00");
if (result.Success == true)
{
DateTimeZone source_zone = DateTimeZoneProviders.Tzdb.GetZoneOrNull("Europe/Brussels");
DateTimeZone target_zone = DateTimeZoneProviders.Tzdb.GetZoneOrNull("Australia/Melbourne");
if (source_zone != null && target_zone != null)
{
ZonedDateTime source_zoned_dt = result.Value.InZoneStrictly(source_zone);
Console.WriteLine(source_zoned_dt.ToInstant());
Console.WriteLine(source_zoned_dt);
Console.WriteLine(source_zoned_dt.WithZone(target_zone));
}
else
{
Console.WriteLine("time zone not found");
}
}
else
{
Console.WriteLine("parsing failed");
}
I'm working on formatting datetime's to display on a graph, and its working great so far. I have the format string:
M/dd/yyyy HH:mm:ss
and it prints as I'd like it to except the following: I want to completely hide the HH:mm:ss if the time is midnight.
Is it possible to do without a custom iformatprovider?
Thanks!
DateTime time = DateTime.Now;
string txt = time.ToString(time == time.Date ? "M/dd/yyyy" : "M/dd/yyyy HH:mm:ss");
DateTime time = DateTime.Now;
string format = "";
if (time.Hour == 0)
{
format = "M/dd/yyyy";
}
else
{
format = "M/dd/yyyy HH:mm:ss";
}
A culture-independent version of the solution proposed by #JDunkerley would be:
DateTime time = DateTime.Now;
string txt = time.ToString(time == time.Date ? "d" : "g");
More about standard date and time format strings here.
The proposed solution is not a very good one because it does not take into account user's localized time format, and simply assumes US English.
Here's how it should've been done:
public static string formatDateTimeWithTimeIfNotMidnight(DateTime dt)
{
//RETURN:
// = String for 'dt' that will have time only if it's not midnight
if (dt != dt.Date)
{
//Use time
return dt.ToString();
}
else
{
//Only date
return dt.ToShortDateString();
}
}