my input is date.
But, i'm stuck on how to retrieve date time in every second.
I need to put the each second date time in the 2d array.so my array(0,0) should equal to 2/10/2014 00:00:00 AM and array(86399,0) is equal to 2/10/2014 23:59:59 PM.
i tried do looping as per below code:
Dim twoDarray(86399, 1) As String
Dim dtInput As Date
dtInput= #2/10/2014#
For i=0 to 86399
twoDarray(i, 0) = dtInput
dtInput = dtInput +second 'i know this not right
Next
I just don't know how to increase date time every second in right way.
Please help.
Have you thought about something along the lines of
Using a Datetime (MSDN Datetime)
dtInput= new DateTime(2014,10,2)
For i=0 to 86399
twoDarray(i, 0) = dtInput
dtInput = dtInput.AddSeconds(1)
Next
Or
dtInput= new DateTime(2014,10,2)
For i=0 to 86399
twoDarray(i, 0) = dtInput.AddSeconds(i+1)
Next
You can try following method also
Dim dtFrom As New DateTime(2014, 10, 2, 0, 0, 0)
Dim dtTo As New DateTime(2014, 10, 2, 23, 59, 59)
Dim iFirstDim As Integer = (dtTo - dtFrom).TotalSeconds
Dim iSecondDim As Integer = 10
Dim arrTime(iFirstDim, iSecondDim) As String
Dim i As Integer = 0
Do While (dtTo > dtFrom)
arrTime(i, 0) = dtFrom.ToString("d/MM/yyyy HH:mm:ss")
dtFrom = dtFrom.AddSeconds(1)
i += 1
Loop
HOW TO USE IT?
Dim dtResult As DateTime
If DateTime.TryParseExact(arrTime(150, 0), "d/MM/yyyy HH:mm:ss", Globalization.CultureInfo.InvariantCulture, Globalization.DateTimeStyles.None, dtResult) Then
MsgBox(dtResult.ToString("yyyy-MM-dd HH:mm:ss"))
End If
Related
Good day. There is the following code that subtracts from one date another:
Dim dt As New DateTime(2021, 8, 19)
Dim dt2 As New DateTime(2022, 8, 29)
MsgBox("Days Remaining : " & (dt2 - dt).Days)
tell me how to subtract format dates:
19.08.2021 14:07:16 - 24.08.2021 08:24:01
throwing away the time. I'm only interested in how to subtract dates of this format.
Date and time are entered in text boxes
You would get the Date property (documentation) of the DateTime values. Also, I would probably recommend using DateTime.Subtract (documentation) which would return a TimeSpan value.
Take a look at this example:
Dim dt = New DateTime(2021, 8, 19)
Dim dt2 = New DateTime(2022, 8, 29)
Dim daysLeft = dt2.Subtract(dt).Days
Example: https://dotnetfiddle.net/LMuWtu
You have to parse the formatted Dates then use .Date to keep only the Date part and throw away the time. Then you can substract and use TotalDays:
Dim input1 As String = "19.08.2021 14:07:16"
Dim input2 As String = "19.08.2021 14:07:16"
Dim d1 As DateTime = DateTime.Parse(input1).Date
Dim d2 As DateTime = DateTime.Parse(input1).Date
Dim days As Single = (d1 - d2).TotalDays
The formatted dates should match your Culture format. You can also use Parse overload to use another Culture : https://learn.microsoft.com/fr-fr/dotnet/api/system.datetime.parse?view=net-5.0#System_DateTime_Parse_System_String_System_IFormatProvider_
I am using VB.NET. I have a dropdownlist named startTimeDDL. Than I am using loop to enter in time inside that dropdownlist.
' Auto fill "Start Time" for DropDownList
Dim StartTime As DateTime = #12:00:00 AM#
For i As Integer = 0 To 47
StartTimeDDL.Items.Add(StartTime.ToString("hh:mm tt"))
StartTime = DateAdd(DateInterval.Minute, 30, StartTime)
Next
So look below and that will be inside the dropdownList. notie the format is hh:mm am/pm.
12:00 AM
12:30 AM
01:00 AM
01:30 AM
02:00 AM
...
11:30 PM
Problem:
lets say current time is 1:21:01 pm than I want to write code so it select 1:30 pm from dropdownlist. Now les take another example. les say current time is 12:00:00 AM than I was to select 12:30 AM from dropdownlist. les take one last example. les say current time is 2:10:12 AM than I want to select 2:30 AM from the dropdownlist.
here is the code I wrote so far. problem with it is that I am only selecting the current time. now can I modfily to do what I want?
Dim dDate As DateTime = DateTime.Now.ToString("hh:mm tt")
Dim temp As String = dDate
StartTimeDDL.Items.FindByValue(temp).Selected = True
Round up if the minute value exceeds 30, round down if it's lower.
Here is an example implementation, you'll need to decide what to do with the "exactly 30 minutes past the hour" edge case. In my code it'll round up for that too.
Private Function RoundDateToHalfHours() As Date
Dim current As DateTime = DateTime.Now
Dim ts As TimeSpan
If current.Minute >= 30 Then
ts = New TimeSpan(current.Hour + 1, 0, 0)
Else
ts = New TimeSpan(current.Hour, 30, 0)
End If
Return current.Date.AddTicks(ts.Ticks)
End Function
Usage:
Dim roundedDate As DateTime = RoundDateToHalfHours()
StartTimeDDL.Items.FindByValue(roundedDate.ToString("hh:mm tt")).Selected = True
You are playing fast and loose with DateTime when you should be using TimeSpan, some caution required. The general way to round up an integral number to an arbitrary interval is
roundedUp = interval * ((number + interval - 1) \ interval)
Which you can readily use on DateTime as well by converting it to ticks, a one-liner
Public Function RoundupDate(dt As DateTime, interval As TimeSpan) As DateTime
Return New DateTime(interval.Ticks * ((dt.Ticks + interval.Ticks - 1) \ interval.Ticks))
End Function
Sample usage:
Dim example = #2:10:12 AM#
Dim rounded = RoundupDate(example, TimeSpan.FromMinutes(30))
Wasn't sure what you meant by a 'dropdownList'. For this example I used a ComboBox.
Dim StartTime As DateTime = #12:00:00 AM#
'load combo box
Do
StartTimeDDL.Items.Add(StartTime.ToString("hh:mm tt"))
StartTime = StartTime.AddMinutes(30)
Loop While StartTime.TimeOfDay.TotalDays > 0
Dim selectTime As DateTime = #2:10:12 PM# 'TEST find this <<<<<<<<<<<<<<<<<<<
'round time to 30 minutes
Dim numSecs As Integer = (CInt(selectTime.TimeOfDay.TotalSeconds) \ 1800) * 1800
'the OP said 'les say current time is 12:00:00 AM than I was to select 12:30 AM"
'so....
numSecs += 1800 'round up 30 minutes ????????
'create 'find'
Dim ts As New TimeSpan(0, 0, numSecs)
Dim findDate As New DateTime(ts.Ticks)
StartTimeDDL.SelectedIndex = StartTimeDDL.FindStringExact(findDate.ToString("hh:mm tt"))
I am trying to subtract hours and minutes from a DateTime variable and I have found other posts that show that you should be able to use the .AddHours(-3) in order to achieve this but it is not working for me. I am grabbing the datetime from a DateTimePicker control in vb.net. say the time is 10:00 AM, I want to subtract 3 hours from this to make it 7:00 AM. My hours variable evaluates to -3 but even when I just literally put the number -3 inside the .AddHours it still does not subtract the time. Heres the code
Dim ApptTime As DateTime = Convert.ToDateTime(DateTimePicker2.Value)
Dim travelTime As String = Label60.Text
Dim newtime As Double
Dim split() As String = travelTime.Split(" ")
If split.Length = 2 Then
Dim Minutes As String = split(0).Replace("mins", "")
Else
Dim Hours As Double = split(0).Replace("Hours", "")
Dim Minutes As Double = split(2).Replace("mins", "")
Hours = -Hours
Minutes = -Minutes
ApptTime.AddHours(Hours)
ApptTime.AddMinutes(Minutes)
Label62.Text = (ApptTime.ToString)
It's simple error ...
Dim ApptTime As DateTime = Now
'ApptTime.Subtract(New TimeSpan(1, 60, 60)) 'won't work
ApptTime = ApptTime.Subtract(New TimeSpan(1, 60, 60)) '1h , 60m , 60s
Try this:
Dim NowMinusThreeHours = DateAdd(DateInterval.Hour, -3, Now)
How would I make my application do an event when there is a certain date? I can't seem to find something that works. Year doesn't matter, just day and month is all I need.
Since day and month is all you want to match on:
Dim myDate As Date = Date.Now
Dim someMonth As Integer = 4
Dim someDay As Integer = 13
If myDate.Month = someMonth AndAlso myDate.Day = someDay Then
... month and day are matched
End If
Use IsDate....
If IsDate(MyDate) Then.....
Update various ways of defining date
'DateTime constructor: parameters year, month, day, hour, min, sec
Dim MyDate1 As New Date(2012, 12, 10, 12, 0, 0)
'initializes a new DateTime value
Dim MyDate2 As Date = #12/10/2012 12:00:52 AM#
'using properties
Dim MyDate3 As Date = Date.Now
Dim MyDate4 As Date = Date.UtcNow
Dim MyDate5 As Date = Date.Today
Try something like this:
Dim thisDate As Date = New Date(2014, 4, 13) ' Assuming this is provided
Dim certainDate As Date = New Date(2013, 4, 13) ' Assuming this is provided
If thisDate = New Date(thisDate.Date.Year, certainDate.Month, certainDate.Day) Then
Debug.Print("dates equal excluding year")
Else
Debug.Print("dates UNequal excluding year")
End If
Rememebr, this will always create a new date object for comparison but it works.
Hope it helps!
i try loop while with datetime each on weekly in VB.NET 2008.
This Code
Private Sub Button1_Click()....
'Select DateTime
Dim strDate As Date = dateTimePicker.Value.ToString("yyyy-MM-dd")
'one week (+7)
Dim strDateWeek As String = DateAdd("d", +7, dateTimePicker.Value.ToString("yyyy-MM-dd"))
'DateCurrent
Dim strDateNow As String = DateAdd("d", 0, Now.ToLongDateString())
'While strDate < strDateNow
'ListBox1.Items.Add(strDateWeek)
'End While
ListBox1.Items.Add(strDateWeek)
End Sub
Example
I select on datetimepicker at "04/02/2013"
Output now: 11/02/2013
But I need Output each on weekly
11/02/2013
18/02/2013
25/02/2013 >>> To Current Week
I try loop While, But don't work.
Thanks you for your time. :)
You could do a while loop until the datetime is greater than today?
You want to use DateTime rather than Date, so you can compare to a DateTime.Now
You want to set your actual DatePicker value to a variable, else it will always be the same and you will just get an infinite loop.
Dim datePickerValue As DateTime = DateTimePicker.Value
Dim strDate As Date = DateTimePicker.Value.ToString("yyyy-MM-dd")
Dim strDateWeek As String
Dim strDateNow As String = DateAdd("d", 0, Now.ToLongDateString())
While datePickerValue < DateTime.Now()
strDateWeek = DateAdd("d", +7, datePickerValue.ToString("yyyy-MM-dd"))
datePickerValue = DateAdd("d", +7, datePickerValue.ToString("yyyy-MM-dd"))
ListBox1.Items.Add(strDateWeek)
End While
Just done it on my VS using your naming conventions and this works fine for me
It's been a long time since I didn't have used VB, but maybe I can help?
In your code, using while could be a wrong choice perhaps you could use a for with a break instead.
for I = 1 to 10
Dim strDateWeek As String = DateAdd("d", +7 * i, dateTimePicker.Value.ToString("yyyy-MM-dd"))
.
.
.
or
while(...)
I += 1
Dim strDateWeek As String = DateAdd("d", +7 * i, dateTimePicker.Value.ToString("yyyy-MM-dd"))
Hope that helps.
Try this:
Dim dtAux As Date = dateTimePicker.Value
Dim dtEnd As Date = Date.Today.AddDays(7 - dt.DayOfWeek)
While dtAux <= dtEnd
ListBox1.Items.Add(dtAux.ToString("yyyy-MM-dd"))
dtAux = dtAux.AddDays(7)
End While
The date dtEnd is the last day of the current week, if you want the loop to stop on the current date simply change the while condition to:
While dtAux <= Date.Today