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Check if todays date exists in a table with Entity Framework

I have a database table with columns of type dateTime.
Now I need to see if there already is a row with today's date, but I don't know how to compare the column with the current date without the hour, minutes, seconds.
Basically I have 2022-02-04 14:06:21.080 and I need to check if there is a row created on 2022-02-04.
I'm looking for something like
if (db.dates.Where(x => x.SentDate == Date.Now).Count() > 0)
{
// Do something
}
else
{
// Do something else
}
I only need to see if it has a date from today it doesn't matter what time it was created.
Any help is much appreciated!

If you're filtering for a specific date you can use the DateTime.Date property on both DateTime objects. This will compare the date component of the DateTime:
db.dates.Where(x => x.SentDate.Date == DateTime.Now.Date)
// or
db.dates.Where(x => x.SentDate.Date == DateTime.Today)
If you have a nullable DateTime? column, then you use the Value property along with HasValue:
db.dates.Where(x => x.SentDate.HasValue
&& x.SentDate.Value.Date == DateTime.Today)
Unfortunately, expression trees do not support the null propagation operator ?. so we need to use the above method instead.
DateTime.Date can also be used for date ranges, but take care with the upper bound.
PS: DateTime.Today is the same as DateTime.Now.Date

You can check a date range
var today = DateTime.Today;
var tomorrow = today.AddDays(1);
if(db.dates.Where(x => x.SentDate >= today && x.SentDate < tomorrow) ...
The DateTime.Today Property gets the current date with the time component set to 00:00:00.

You can check a date range
var today = DateTime.Today;
var tomorrow = today.AddDays(1);
if(db.dates.Where(x => x.SentDate >= today && x.SentDate < tomorrow) ...
The DateTime.Today Property gets the current date with the time component set to 00:00:00.
Note that we test the lower bound with >= today (with today meaning today at 00:00:00) but the upper one with < tomorrow, since we do not want to include tomorrow at 00:00:00.

Another way is to convert the dates to string and compare.
if(db.dates.Any(m=>m.SentDate.ToString("d") == DateTime.Now.ToString("d"))){
//Do something else
}
else
{
// Do something else
}

If you use MS SQL Server you can use a special function EF.Functions.DateDiff that was created to be used with EF. It can count datetime difference from seconds to months. DateDiffDay is used to count days.
var dateTimeNow = DateTime.Now;
if (db.dates.Any(x => EF.Functions.DateDiffDay(x.SentDate , dateTimeNow) == 0 )
{
// ... there are today's dates
}
// ...

compare two dates time hours and minutes (not secs)?

This is may be silly question. But I am missing logic here. I have to compare dates with date time with hours and minutes (not with seconds).
IF first field time is older then second field execute condition
right now I am doing if (Convert.ToDateTime(newItem["Modified"]) < Convert.ToDateTime(properties.ListItem["Modified"]))
example if("02/12/2015 11:58" < "02/12/2015 12:01") then execute condition.

You could create new DateTime objects with mostly the same values, but with seconds set to 0. Example:
DateTime date1WithoutSeconds = new DateTime(dt1.Year, dt1.Month, dt1.Day, dt1.Hour, dt1.Minute, 0);
DateTime date2WithoutSeconds = new DateTime(dt2.Year, dt2.Month, dt2.Day, dt2.Hour, dt2.Minute, 0);
bool b = date1WithoutSeconds < date2WithoutSeconds;

You could subtract the two dates, and if the TotalSeconds of the difference is less than 60 AND the minues are the same, then they are equal:
var first = Convert.ToDateTime(newItem["Modified"]);
var second = Convert.ToDateTime(properties.ListItem["Modified"]);
if (first.Subtract(second).TotalSeconds < 60 && first.Minute == second.Minute)
{
Console.WriteLine("They are equal");
}

You should use the DateTime.CompareTo method.
Grab and assign both dates as DateTime objects:
DateTime date = Convert.ToDateTime(newItem["Modified"]);
DateTime compareDate = Convert.ToDateTime(properties.ListItem["Modified"]);
You can now use the CompareTo method of the DateTime object to see if the instance is earlier, the same, or later than the other, returning -1, 0, and 1 respectively.
So, following your example: if("02/12/2015 11:58" < "02/12/2015 12:01"), first date being date and second being compareDate, the code:
date.CompareTo(compareDate);
will return -1, telling you the instance invoking the method is earlier than the object you are comparing it to.
Here is the MSDN.

One more way that should work.
DateTime date1 = Convert.ToDateTime(newItem["Modified"]);
DateTime date2 = Convert.ToDateTime(properties.ListItem["Modified"]));
if( date1.AddSeconds(-date1.Second) < date2.AddSeconds(-date2.Second) ) {
}
But, I would wonder...is it really that you need to ignore the seconds and "floor" the result so that 12:59:00 is the same as 12:59:59 but different than 12:58:59 even though there's only a second of difference...or do you need to know that it's greater than a minute of difference? If you really just want to make sure that it is a minute apart, use TimeSpan (date1 - date2).TotalSeconds > 60
I doubt this is likely, but if your DateTime is a string WITH milliseconds, then do:
if( date1.AddSeconds(-date1.Second).AddMilliseconds(-date1.Millisecond) <
date2.AddSeconds(-date2.Second).AddMilliseconds(-date2.Millisecond) )
{
}

First of all, the sample data you've mentioned in your question doesn't include seconds, so by default Convert.ToDateTime will assign '00' as seconds, so it would compare without the seconds.
But let's say that you do provide seconds in the actual data. You can use the following:
var date1 = Convert.ToDateTime(newItem["Modified"]);
var date2 = Convert.ToDateTime(properties.ListItem["Modified"]);
if (date1.AddSeconds(-date1.Second) < date2.AddSeconds(-date2.Second))

DateTime comparison not including the most recent date

I'm trying to understand why the following function doesn't work.
public IEnumerable<LogFile> GetLogs(string directory, DateTime start, DateTime end)
{
DirectoryInfo di = new DirectoryInfo(directory);
return di.GetFiles("*debug.log").Where(f => f.LastWriteTime > start && f.LastWriteTime <= end).Select(f => new LogFile(f.FullName));
}
Why does the second comparison (f.LastWriteTime <= end) omit the specified end date?
The first comparison (f.LastWriteTime > start) does include the specified start date.
For exampled, if I set the start date to 1/4/2013 and the end date to 1/8/2013 the function return files with the following dates:
1/4/2013,
1/5/2013,
1/6/2013,
1/7/2013
It will not include 1/8/2013, despite the use of <= in the code.

You're dealing with date & time values, not just date values.
1/6/2013 4:30 is not equal to 1/6/2013 12:00, despite the fact that the dates are the same.
You can use the Date property on each of the DateTime objects to get new DateTime objects where the time is always midnight.

DateTime contains (as its name implies) also time component. So your comparison actually is:
f.LastWriteTime > start && f.LastWriteTime <= end
f.LastWriteTime > 1/4/2013 00:00:00 && f.LastWriteTime <= 1/8/2013 00:00:00
The last file date is probably something like 1/8/2013 13:45:12 so
1/8/2013 13:45:12 <= 1/8/2013 00:00:00
is false.
Because of the time component the first date acctualy is included in result:
1/4/2013 00:00:00 > 1/4/2013 13:45:12
is true.

But when compare with date plue time, the last second of value is not included: time <= 1/14/2013 1:26:42 am, it include 1/14/2013 1:26:41 AM ?

c# get all dates from database that appear with current week

trying to get all the dates from the db that are within the current week
i have email1DueDate, email2DueDate, email3DueDate
and i want to see if they are due to be sent within the current week

First you should calculate two DateTime values for the start of the week and the end of the week, you can do that like this (assuming Monday is the first day):
DateTime startOfWeek = DateTime.Today;
int delta = DayOfWeek.Monday - startOfWeek.DayOfWeek;
startOfWeek = startOfWeek.AddDays(delta);
DateTime endOfWeek = startOfWeek.AddDays(7);
next you can use this in your LINQ query to get the results you need, I am assuming you want results to be rows that have any of your due dates fall in the week:
var results = DB.Table.Where(x =>
(x.email1DueDate >= startOfWeek && x.email1DueDate < endOfWeek) ||
(x.email2DueDate >= startOfWeek && x.email2DueDate < endOfWeek) ||
(x.email3DueDate >= startOfWeek && x.email3DueDate < endOfWeek)
);
If this is not what you need then you will need to clarify your requirements

LINQ
listOfDates.Where(x => x.email1DueDate > beginOfWeekDate && x.email1DueDate < endOfWeekDate).ToList();
Of course you'll still have to figure out the begin and end dates

C# DateTime falls within the last 24 hours

I have a DateTime object that I'd like to check and see if it falls within the last 24 hours.
I did something like this but its wrong:
myDateTime > DateTime.Now.AddHours(-24) && myDateTime < DateTime.Now
where did I go wrong?

There is nothing wrong with the code that you posted, so whatever you did wrong is somewhere else in the code.
I only see two minor flaws in the code, but they only affect corner cases:
You should avoid getting the DateTime.Now property repeatedly in the code. Its value changes, so you may get inconsistent results in some cases when the values changes from one use to the next.
To get a time interval you would usually pair one inclusive and one exclusive operator, like > and <=, or >= and <. That way you can check for intervals next to each other, like 0 - 24 hours and 24 - 28 hours, without getting a gap or an overlap.
DateTime now = DateTime.Now;
if (myDateTime > now.AddHours(-24) && myDateTime <= now)

Only get DateTime.Now once within the function - otherwise the value might change.
Use <=, not <. if you check a microsecond after the time has been set, it will still be equal to DateTime.Now. I actually ran into this in production code where imports wouldn't show up in a different query that checked < because the import was too fast!
Use this code:
DateTime now = DateTime.Now;
DateTime yesterday = now.AddDays(-1);
if (myDateTime > yesterday && myDateTime <= now) {
...
}

Learning from both the above answers and also to improve the readability of the code we can use a method like this.
using System;
public class Program
{
public static void Main()
{
DateTime myDateTime = DateTime.Parse("2021-08-25T20:20:19.5540211");
DateTime now = DateTime.Now;
DateTime yesterday = now.AddHours(-24);
if (IsBewteenTwoDates(myDateTime, yesterday, now))
{
Console.WriteLine("this date ({0}) is between {1} & {2}", myDateTime, yesterday, now);
}
else
{
Console.WriteLine("this date ({0}) is not between {1} & {2}", myDateTime, yesterday, now);
}
}
// Checks if the DateTime object dt is between start and end DateTime.
public static bool IsBewteenTwoDates(DateTime dt, DateTime start, DateTime end)
{
return dt >= start && dt <= end;
}
}
Check the fiddle here.