Date time format convert in vb.net - vb.net

I'm getting date-time from a source as 20110731183330. I want to convert it to '7/31/2011 06:33:30 PM'. Is there a one line code for the same in vb.net?

That would be:
Dim result As Date = Date.ParseExact(datestring, "yyyyMMddHHmmss")

It can be...
Dim CustomDate As Date = Date.ParseExact(yourdate, "MM/dd/yyyy hh:mm:ss tt", Globalization.DateTimeStyles.None)

Dim result As Date = Date.ParseExact(dt, "yyyyMMddHHmmss", System.Globalization.CultureInfo.InvariantCulture)
then we can format it as required.

Related

Differences between date formatting in VBA

I'd like to achieve the result seen in A1. How come line 3 doesn't output the same result as line 1 & 2 even though the format is the same - yyyy-mm-dd hh:mm:ss?
Does this have anything to do with regional settings?
1 Range("A1").Value2 = Now
2 Range("A1").NumberFormat = "yyyy-mm-dd hh:mm:ss"
3 Range("B1").Value2 = Format(Now, "yyyy-mm-dd hh:mm:ss")
That is because:
A1: You set a Date value and apply a specific format for display.
B1: You format a Date value to Text, set that as the value, but the cell has been applied no specific format, thus Excel sees the text date as a date value and casts it to a true Date value, which is displayed with your default (German?) date format.
To force the text date to be read as text, you could prefix it with a quote:
Range("A1").Value2 = Now
Range("A1").NumberFormat = "yyyy-mm-dd hh:mm:ss"
Range("B1").Value2 = Format(Now, "yyyy-mm-dd hh:mm:ss")
Range("C1").Value2 = Format(Now, "\'yyyy-mm-dd hh:mm:ss")
Output (Danish localisation):
Note, that C1 is text (left-aligned).
Why you not set, before or after, your cell formatting with a Range?
Example:
Range("A1:Z1").NumberFormat = "yyyy-mm-dd hh:mm:ss"
Range("A1").Value2 = Now
Range("B1").Value2 = Now

Datetime add timespan without showing the date VB

I am currently running this code, and it displays the date as Output shown below.
Dim started As DateTime = DateTime.Now
Dim date As DateTime = started.Add(diaryItem.Duration)
Output : 23/03/2016 17:00:00
Is it possible to remove the date and only show the time ?
If you only want to see time from datetime then try this:
'show time
Dim OnlyTime As String = DateTime.Now.ToString("hh:mm:ss")
'or
Dim OnlyTime = DateTime.Now.ToShortTimeString
If you only want to see date from datetime then try this:
'show date
dateOnly = myDateTime.Date
'or
dateString = dateOnly.ToShortDateString()
If this is not what you are looking for then put more informations..
DateTime Structure

DateTime change date value and set specific value of time in VB.Net

I have value of this for example
Dim start_time As String = 12/30/1899 8:30:00 PM
Then i want to change it into
Dim final_start_time As String = 0000-00-00 20:30:00 ' i want to come up with this value
or another example is
Dim start_time As String = 12/30/1899 10:30:00 AM
to
Dim final_start_time As String = 0000-00-00 10:30:00
Based on your revised Question, here is some code. Revise it as necessary. I used es-ES as culture.. actually have no clue what culture that is... but on the dateformat MSDN page, that seems to generate the format you want...
Dim myOriginalDateTime As DateTime = Now
Dim mynewDateString As String = ""
Dim myFinalDateString As String = ""
Dim culture As New System.Globalization.CultureInfo("es-ES")
mynewDateString = myOriginalDateTime.ToString("G", culture)
Dim arrDateParts() As String = Split(mynewDateString, " ")
myFinalDateString = "0000-00-00 " & arrDateParts(1)
MsgBox(myFinalDateString)
Try this link:
http://msdn.microsoft.com/en-us/library/zdtaw1bw(v=vs.110).aspx
And this:
http://msdn.microsoft.com/en-us/library/vstudio/az4se3k1(v=vs.100).aspx
You use the .tostring method, and specify a format.

Date format parsing using Now()

I need to compare dates in winforms, using vb.net
I am trying using
If Now() = DateTime.Parse("17.01.2013 08:47:10 PM")
The problem is my date is in dd/mm/yyyy format but when this application runs on a system where the format is mm/dd/yy, it gives problem.
How can I bring the system date (obtained using NOW()) in dd/mm/yyyy format so it could be compared with my given date?
Thanks
Try using DateTime.ParseExact or TryParseExact:
Dim date As Datetime = DateTime.ParseExact(_
"17.01.2013 08:47:10 PM", "dd.MM.yyyy hh:mm:ss tt", CultureInfo.InvariantCulture)
Good luck.
I try to use the format "yyyy-MM-dd HH:mm:ss" as this works with any dateformat and also with SQL. See below:
Private Shared Sub DateCompare()
Dim myDate As Date = "12/07/2013 21:31:34"
Dim nowDateString As String = Format(Now, "yyyy-MM-dd HH:mm:ss")
Dim myDateString As String = Format(myDate, "yyyy-MM-dd HH:mm:ss")
If nowDateString = myDateString Then
MessageBox.Show("Matches")
End If
End Sub
Try something like that:
if (Now().ToString("MM/dd/yy") = myDate)
Careful of "MM" and "mm" in vb formatting.

date not formatting correctly on a date that does not exist

I have the following code to convert a date (from a database entry) into the correct format:
Dim blah As Date = "02/29/2001"
MsgBox(Format(blah, "yyyy-MM-dd"))
However, it keeps telling me this:
Conversion from string "02/29/2001" to type 'Date' is not valid.
Now i see that 2/29/2001 does not have a day 29- only 28 for that year. So how would i check for this so it doesn't throw an error when a date in the database table is not entered correctly?
You can use IsDate()
This function returns true if your string or date can be converted to date.
like this
Dim dateAndTime As String
dateAndTime = "March 15, 1981 10:22 AM"
noDate = "Hello"
dateCheck = IsDate(dateAndTime)
dateCheck = IsDate(noDate)
This will return true for the first one and false for the second one
Also, this function works with month of 29, 30 or 31 days like in your case
here's the msdn link
You could use TryParseExact instead, so something like:
Dim enUS As New CultureInfo("en-US")
Dim dateString As String
Dim blah As Date
' Parse date with no style flags.
dateString = "02/29/2001"
If Date.TryParseExact(dateString, "MM/dd/yyyy", enUS, DateTimeStyles.None, dateValue) Then
MsgBox(Format(blah, "yyyy-MM-dd"))
Else
MsgBox(String.Format("'{0}' is not in an acceptable format.", dateString))
End If