I have user input that needs to be verified that the string is in the datetime format as follows:
yyyy-MM-dd HH:mm:ss
The user does not have a choice for any other format but for error checking how do I detect whether string in is this format.
sDate = DateTime.ParseExact(startDate, "yyyy-MM-dd HH:mm:ss", CultureInfo.CurrentCulture)
startdate is the string.
This code will help you to convert the date into the format which which you wanted to check
Dim format As String = "yyy-MM-dd HH:mm:ss" 'let input be "02-02-2014 12:12:12"
MsgBox(dt.ToString(format)) ' the output will be 2014-02-02 12:12:12
it works properly in VS 2010(windows 7)
IMHO, you should consider using DateTimePicker control for taking date/time input. Use Custom Format (if needed). It will save you to first take it and validate it.
You should use DateTime.TryParseExact if you want the date/time format to be exactly in a particular format.
Function IsValidDate(ByVal dateValue As String) As Boolean
Return DateTime.TryParseExact(dateValue, "yyyy-MM-dd HH:mm:ss", CultureInfo.InvariantCulture, DateTimeStyles.None, Nothing)
End Function
Related
I need to convert a dd/mm/yy date to dd/mm/yyyy automatically.
Example: if I insert in the textbox "12/01/90", the program should automatically convert the text to "12/01/1990" or "01/01/20" to "01/01/2020".
Also, I should check the date to make sure it is correct.
Example: if I enter "80/70/2000" it must give me an error because the date does not exist. How can I do? Thanks in advance.
If you have the input as a string, you would first parse it into a date with the format specifier, and then convert it back into a string.
Dim input as String = "22/03/19" ' dd/mm/yy
Dim dt as DateTime = DateTime.MinValue
If (DateTime.TryParseExact(input,
"dd/MM/yy",
System.Globalization.CultureInfo.InvariantCulture,
System.Globalization.DateTimeStyles.None,
dt
)) Then
Dim output as String = dt.ToString("dd/MM/yyyy")
Console.WriteLine(output)
else
Console.WriteLine("Error")
end if
Output:
22/03/2019
You can try it here
is there anyway to convert "20180717" in to datetime "MM dd yyyy" format in vb.net
im reading csv file and pick up values related to date all date values are in like "20180717" format need to store thoses in datatable DateTime column in sql
You can also use DateTime.TryParseExact. This method doesn't throw an Exception in case the input isn't valid:
Dim dtValue As DateTime
If DateTime.TryParseExact("20180717", "yyyyMMdd", CultureInfo.InvariantCulture, Globalization.DateTimeStyles.None, dtValue) Then
'The input is a valid date in specified format. The parsed date is now in dtValue
Else
'The input isn't a valid date (in specified format).
End If
DateTime.ParseExact(csvstring,"yyyyMMdd",CultureInfo.InvariantCulture).ToString("MM dd yyyy")
I have referred to solutions provided for date in yyyy-MM-dd format. After providing the format also, I am getting date in default format. Please help.
code:
Dim returndate As String
returndate = DateTime.Now.ToString("yyyy-MM-dd")
Dim oDate As DateTime = DateTime.ParseExact(returndate, "yyyy-MM-dd", CultureInfo.InvariantCulture)
As it stands I'm guessing your output of oDate is 27/01/2017 00:00:00.
What you want to do is this:
Dim returndate As String = DateTime.Now.ToString("dd/MM/yyyy")
Dim oDate As DateTime = DateTime.ParseExact(returndate, "dd/MM/yyyy", CultureInfo.InvariantCulture)
Debug.Print(oDate.ToString("yyyy-MM-dd"))
Send the returndate into DateTime.ParseExact with the format of "dd/MM/yyyy" and then format oDate to the desired output, in your case "yyyy-MM-dd".
This is a screenshot of the code and output:
Dates don't inherently have a format. The format you pass to ParseExact is the format it expects of the first parameter, in your case returndate. It's not the output format. Have a look over the DateTime.ParseExact documentation:
format
A format specifier that defines the required format of s. For more information, see the Remarks section.
Looking at the Remarks section:
The DateTime.ParseExact(String, String, IFormatProvider, DateTimeStyles) method parses the string representation of a date, which must be in a format defined by the format parameter. It also requires that the date and time elements in s appear in the order specified by format. If s does not match the pattern of the format parameter, with any variations defined by the style parameter, the method throws a FormatException.
I'm taking date from my csv file
Dim odateq As String = sData(0).Trim()
I am getting odateq as 9/15/2015
I want to convert this to 15/9/2015. So I wrote code like this
Dim newdate As DateTime = DateTime.ParseExact(odateq, "dd/MM/yyyy", System.Globalization.CultureInfo.CurrentCulture)
And I'm getting an error like this :
String was not recognized as a valid DateTime.
any help is very appreciable...thanks
the code you wrote is using the wrong format; the date you have is in the format M/d/yyyy (month and day without leading zero are a guess because you did not specify it).
try with this one:
Dim newdate As DateTime = DateTime.ParseExact(odateq, "M/d/yyyy", System.Globalization.CultureInfo.CurrentCulture)
the format you set in the ParseExact was telling the function to expect a date in the format dd/MM/yyyy like 01/05/2015 but what you have is not in that format.
after you parse the input date, to get a string with format dd/MM/yyyy use:
Dim dateAsText As String = newdate.ToString("dd/MM/yyyy")
I followed suggestion from vb.net convert string to date . But, it did not work.
the code is as follows:
Dim Dt As DateTime
If DateTime.TryParse("Thu, 09 Dec 2010 16:03:24 EST", Globalization.CultureInfo.InvariantCulture, Globalization.DateTimeStyles.None, Dt) Then
MessageBox.Show(Dt)
End If
Can anyone solve this for me? I need to have date populated in the format of "yyyy-mm-dd hh24-mi-ss".
this should get you on the right path:
Dim dt As DateTime
dt = Now
TextBox1.Text = Format(dt, "yyyy-MM-dd HH:mm:ss")
NOTE: this answer was written for a previous revision of the question which had the following code:
Dim Dt As DateTime
If DateTime.TryParseExact("Thu, 09 Dec 2010 16:03:24 EST", "dd.MM.yyyy", Globalization.CultureInfo.InvariantCulture, Globalization.DateTimeStyles.None, Dt) Then
MessageBox.Show(Dt)
End If
The format string that TryParseExact takes as it's second parameter specifies the format of the date in the string passed as the first.
In your case the format string is specifying that the date will be of the format "09.12.2010" for example - just the day, moth and year. However, as the string isn't in that format it won't parse. If you'd just used ParseExact it would have raised an exception.
The MSDN page for the variant of TryParseExact that takes an array of possible format strings has more examples, but non match your format exactly, but working with the format strings used to convert DateTime to string you probably want something like this:
"ddd, dd MMM yyyy HH:mm:ss ???"
but I can't find what you'd need instead of "???" to match the "time zone as string". You might have to do some string manipulation to remove this before calling TryParse or TryParseExact.
You will have to replace the timezone with the timezone offset.
Same question as Parse DateTime with time zone of form PST/CEST/UTC/etc
TextBox1.Text = System.DateTime.Now.AddMinutes(698).ToString("dd/MM/yyyy");
DateTime DOB;
string[] formatsDOB = { "dd/MM/yyyy", "MM/dd/yyyy" };
DateTime.TryParseExact(txtDateofBirth.Text, formatsDOB, CultureInfo.CurrentCulture, DateTimeStyles.None, out DOB);