How to add both date and time in DateTime variable - vb.net

I have two datetime variables in VB.Net
Dim inDt As Datetime //contains date
Dim inTime As DateTime //contains time
I want to add both these variable in single DateTime variable , i didn't find any .Net function to do that.Is there any other way to do it?

Illustrating my comment above, you can do this:
DateTime combinedDateTime = inDt +
new TimeSpan(0, inTime.Hour, inTime.Minute, inTime.Second, inTime.Millisecond);

You could make use of the Ticks property and the AddTicks method:
Dim result As DateTime
result = inDt.AddTicks(inTime.Ticks)

Related

How can i add 1 day to a DateTime variable in Visual Basic?

What im trying to do is to add/sum a single day to an already declared DateTime variable.
For context i take the DateTime value from a user input and then I want to add/sum 1 day for comparison and query purposes.
This is what i had in mind but i know this method wont work.
SQL.AddParam("#FromDate", FromDate + 1)
What would be the proper way to do this?
Dim dateTime As DateTime
dateTime = dateTime.AddDays(1)
Datetime objects provide some functions to add time.
.AddDays(days as Double)
.AddHours(hours as Double)
.AddMinutes(minutes as Double)
.AddSeconds(seconds as Double)
.AddMilliseconds(milliseconds as Double)
Or you can try to pass directly to SQL your date + 1 day.
SQL.AddParam("#FromDate", DateAdd(DateInterval.DayOfYear, 1, FromDate))
Datetime.DateAdd function Microsoft's documentation:
https://learn.microsoft.com/en-us/dotnet/api/microsoft.visualbasic.dateandtime.dateadd?view=netcore-3.1

I can't use datetime subtract method

I can't use following Datetime subtract method.
https://msdn.microsoft.com/ja-jp/library/system.datetime.subtract(v=vs.110).aspx
I use Microsoft Visual Studio Proffesional 2013 and VisualBasic2013 and .NetFrameWork Version 4.5.50938
I want to use above method. I can use Add method like this:
Dim dt As Datetime = Nothing
dt.Add(New TimeSpan(1))
I want to know why although there is the homepage that is Datetime.
Subtract, I can't use subtract method......
Let's see what happens when you try to create a DateTime as Nothing:
Dim dt As DateTime = Nothing
Console.WriteLine(dt.ToString("yyyy-MM-dd HH:mm:ss.fffffff"))
we get "0001-01-01 00:00:00.0000000". This is the earliest datetime that can be represented by a DateTime. It can't hold a "value" of Nothing because it is a Value type: Why is null not allowed for DateTime in C#?.
Let's try adding 1 tick:
dt.Add(New TimeSpan(1))
Console.WriteLine(dt.ToString("yyyy-MM-dd HH:mm:ss.fffffff"))
Oh! We get "0001-01-01 00:00:00.0000000" again. The tick was not added on. That is because the Add method returns a new DateTime - it does not affect the one that Add was invoked on.
Let's try again:
dt = dt.Add(New TimeSpan(1))
Console.WriteLine(dt.ToString("yyyy-MM-dd HH:mm:ss.fffffff"))
Now we get "0001-01-01 00:00:00.0000001", as intended.
What happens if we try to go earlier than the first allowed DateTime?
Dim dt As DateTime = Nothing
dt = dt.Subtract(New TimeSpan(1))
It throws a System.ArgumentOutOfRangeException.

How to convert DateTime to Integer and check the difference?

I'm trying to compare the difference between two times in the day. I'm getting time in UTC format. Do I have to convert DateTime to integer in order to get the difference and if yes how?
This is my code
Dim ct As DateTime = DateTime.UtcNow
Dim int_ct As Integer = Convert.ToInt32(ct)
MsgBox(ct + " | " + int_ct)
If (System.IO.File.Exists(System.IO.Path.GetTempPath.ToString + "\tempfile.data")) Then
Dim time As DateTime = System.IO.File.ReadAllText(System.IO.Path.GetTempPath.ToString + "\tempfile.data")
Dim int_time As Integer = Convert.ToInt32(time)
If ((int_ct - unlockedtime) < int_time) Then 'unlockedtime is Int variable
Return False
Else
Return True
End If
End If
You don't need to do any timezone conversion, just make sure that both date/time values are in the same timezone when you capture them (though I suppose it might be wise use to UtcNow in case the system timezone changes in-between your two measurements.
You don't need to convert values to Int32 to get the difference, just use the DateTime.Subtract method:
Dim old As DateTime = GetOldDateTime()
Dim now As DateTime = DateTime.UtcNow
Dim diff As TimeSpan = now.Subtract( old )
If diff.TotalSeconds > someSecondsValue Then
DoSomething()
End If
Have you tried Datetime.Compare(dt1,dt2)? Depending on how much detail you need this might work for you.
Here is more information on the function:
http://msdn.microsoft.com/en-us/library/system.datetime.compare.aspx?cs-save-lang=1&cs-lang=vb#code-snippet-1
As Dai said you may want to compare difference, but if you just want the date difference you can use the following:
DateDiff(DateInterval.Minute, Date1, date2)
This returns the difference as an integer, you can set whatever date interval you require as the firt parameter.

exclude weekends from datetime

I need to exclude weekends from this line.
If Convert.ToDateTime(e.Row.Cells(4).Text).ToString < DateTime.Now.AddDays(-3) Then
e.Row.BackColor = System.Drawing.Color.FromName("red")
I hope there is an easy way to do this!
Use the following code
DateDiff(DateInterval.Weekday,Date2, Date1)
--Hiren V
I've had to do something similar once.
The trick is to take the strings from your rows, convert them to a DateTime like you have it, then check the DayOfWeek property of the DateTime object.
The DayOfWeek property can be used as such:
DateTime date = new DateTime();
label1.text = date.DayOfWeek.ToString();
With that, just check if the value is equal to a string of "Saturday" or "Sunday".
That should help you filter off your weekends.

DateAdd Function call

In my Windows Form I have a textbox for number of days to add and a textbox that has a date in it... On the button click event I need to use the "DateAdd" function to add the number of days in textbox number of days to the date entered in textxbox date? Can someone give me the correct syntax I have tried this and getting a syntax error.
DateAdd(DateInterval.Day, txtNumDaysTAdd.Text, txtDate.Text)
I than need to display the answer in a messagebox in the Longdate format using the formatdatetime function.
I would rather use .NET's DateTime functions to do this:
Dim myDate As DateTime = DateTime.Parse(txtDate.Text)
Dim daysToAdd As Integer = Integer.Parse(txtNumDaysTAdd.Text)
Dim result As DateTime = myDate.AddDays(daysToAdd)
Don't use DateAdd, it's only there for backwards compatibility with VB6. Use the methods on the DateTime type instead. In VB.NET, the keyword Date is a shortcut for the DateTime type, just as Integer is a shortcut for the Int32 type.
Dim originDate As Date = Date.Parse(txtDate.Text)
Dim daysToAdd As Integer = Integer.Parse(txtDaysToAdd.Text)
Dim result As Date = originDate.AddDays(daysToAdd)
MessageBox.Show(result.ToLongDateString())