Pulling date and time values from excel (CSV) to C# - c#

I’m building a application that monitors information on a website.
The website allows you to save stuff off it as a CSV.
My problem arises when I try to pull time and date information from Excel.
For those who want to see what spreadsheet I am working on:
http://ets.aeso.ca/ets_web/ip/Market/Reports/CSMPriceReportServlet?contentType=html
if you want the spreadsheet:
change the html in the link to csv
I’m having trouble with A6 downward and B6 downward column.
When I pull out the A6 column, the dynamic type is string.
My question regarding this part is:
Is there any way I can parse the string into a DateTime so I can format it in a standard way?
When I pull out the B6 column, the dynamic type for the time (HH:MM:SS AM/PM) becomes double.
Is there any way I can parse the double into a DateTime so I can format it in a standard way as well?
Thanks so much for your time you guys!
Cheers,
-Jeremiah Tantongco

Get .Text rather than .Value

Thanks for the responses!
I did some more digging and was able to solve both my issues.
For parsing a custom time formatted string into a datetime in C#, use:
DateTime.ParseExact(yourString, formatString, null);
format string is the scheme of your custom time formatted string
Ex:
"09/17/2009 14" becomes "MM'/'dd'/'yyyy HH"
For converting datetime from excel that is stored as a double, use:
DateTime.FromOADate(yourDouble);

if the file format is static then you can pull the data as string in first place say a5 + ":" + a6 (09/16/2009 16:15:00) reformate it as per your requirements and save is as datatime

Related

String was not recognized as a valid DateTime from SQLite file

I have a program, that puts the .txt files to a database file (im using system.data.sqlite NuGET package). I have yyyy.MM.dd format set on my Pc, and it's used by the database too, however I still get the above mentioned error.
An additional info, that could help, is that when I set the table's appropriate column to a simple string it's working as normal, but as soon As I set it to date it gives me this exeption.
Can someone please help me?
You seem to be mixing up how a type is formatted into text with the type itself. If a column is typed as date, then its expecting a date, not a text conforming to whatever date format you have in mind.
Its the same is if you try to do the following:
DateTime date = "01.01.2020";
This won't compile, because string, nevermind if it represents a valid formatted date, and DateTime are two altogether different types.
If you are reading from a text file, you first need to convert the formatted string representations to their corresponding DateTime. See DateTime.TryParse method on how to do this. Once you have valid dates in your hands, try pushing those to the DB.

Formatting '[$-F400]h:mm:ss\\ AM/PM' Excel 2007 date time in c#

I'm trying to read Excel 2007+ files in c# but all the libraries I have tried so far (OpenXML, ClosedXML and NPOI) seem unable to parse a cell with the time format correctly.
In Excel the data is formatted as Number > Time and uses '*hh:mm:ss' as it's type.
When I look at the raw value in the libraries it is appearing as 0.0416666666666667. I've followed advice from other posts which suggest using DateTime.FromOADate which (correctly) results in '30/12/1899 01:00:00'.
What I'm really stuck on is how to display the datetime object {30/12/1899 01:00:00} as it is displayed in Excel: '01:00:00'. I can see the Style.DateFormat is set to '[$-F400]h:mm:ss\ AM/PM' but how can I use this to format the DateTime object in C# as a string? The ToString() method doesn't recognise it as a valid format.
A DateTime by definition always has a date and a time. To only have the time you would have to use a TimeSpan. Here is a quick way you can get that.
DateTime originalDateTime = DateTime.Now;
TimeSpan hoursMinutesSeconds = originalDateTime.TimeOfDay;

EPPlus load custom value

I have cell which contains value
7.11.2014
in custom format
dd/mm/yyyy
so in excel it looks like
07/11/2014
when i load it via EPPLus
cellValue = sheet.Cells[row, column].Value.ToString();
it loads the General format value, which is
41950
How can i load the Value 07/11/2014 or other date format with i can work ?
Thank you
Looking over some similar code that I've done before, all you'll need to do is to use DateTime.Parse() and it should come out exactly how you want it.
As I mentioned in the comments Excel saves the actual dates as being a number of days from its epoch date of 1/1/1900 (hence why you keep seeing 41950). .NET code will accept that, and will convert it to the correct date.
OK i got it, this code works
long serialDate = long.Parse(sheet.Cells[r, c].Value.ToString());
cellValue = DateTime.FromOADate(serialDate).ToString("dd-MM-yyyy");
Thank you for help :)

C# to Excel set custom date display and value

Given a certain date, I want to set the value of a cell with a DateTime object, but without the "Time" information. For example, for today the value would just be "29/06/2012" and not "29/06/2012 16:54:36".
Concerning the display, for today's date I want it to be written like this (it is in french, I don't know how it would be in english): "29 juin" and not "29/06/2012".
How can I achieve this?
EDIT : I just took a look at the display formatting I need in Excel, it is "jj mmmm" ("dd mmmm" in C#). But the cell, though taking the value, does not take the formatting. Here is a piece of code:
cell.Value = string.Format("{0:dd/MM/yyyy}", DateTime.Now);
cell.NumberFormat = "jj mmmm";
I also tried:
cell.Value = DateTime.Now;
cell.NumberFormat = "jj mmmm";
In that case, the display formatting is OK, but the cell value contains the Time information, which is not OK.
See this StackOverflow question, and my answer to it. It will allow you to set the custom format for the cell directly in the excel sheet, from there you just need to research what the different date format strings are.
That is only helpful if you are using excel automation though.
Otherwise, formatting the DateTime.ToString output will be better. Once again, researching the different DateStringFormatting options will be helpful to you.
Final option. Directly change the template, not using automation. Goto the cell and manually change the cell format until the display is what you want. This does not change the actual data, just its display.
UPDATE
There are two specific issues to deal with.
Issue one is making sure excel recognizes that this IS a date. To that end, make certain that the date data itself is formatted en-US. Why, because Microsoft is dumb, and doesn't recognize international date formats.
Issue two is the display format for the cell. For a 3 letter abbreviation of the month, use the string d mmm. If you want the full month name, use d-mmmm.
I was testing and noted that excel refused to treat 29/06/2012 16:54:36 as a date, but it accepted 06/29/2012 16:54:36 without an issue. As I said, microsoft is dumb.
just change DateTime.Now to DateTime.Date and the time will be zero'd out
DateTime has a method called ToShortDateString
// Displays Fri 29 Aug
Console.WriteLine(date1.ToString("ddd d MMM", CultureInfo.CreateSpecificCulture("fr-FR")));
This would be a good resource for you: msdn custom date and time format strings

time format on my sql server

my c# program selects a datetime field from database and returns the data like the following:
21/06/2012 4:11:48 p.m.
it is not stored this way though (it's stored like 2012/06/21 15:19:10:000).
my locale is set to English/New Zealand
but when I try to save it back to database
the ISDATE() sql function doesn't like that format and just returns NULL. Do I have any options to set the time format in sql or c#? What in sql or c# is making it put "p.m."? (instead of just "PM", which by the way works)
Summing up the problem
See latest related link
You shouldn't be saving it in the database as text at all - you should be using the relevant data type such as DATETIME, and passing DateTime values from .NET to the database using SQL parameters. If you're using the right data type, the value won't actually be stored as "2012/06/21 15:19:10:000" at all. That may be how you see it in SQL Server Studio or something similar, but that doesn't mean it's the raw storage format.
Logically, a date/time doesn't have a format any more than the number ten is "10" (decimal) vs "A" (hex). Avoid string conversions as far as you can, and your life will be easier.
Note: See Jon's response about properly saving the DateTime in the database rather than a string.
For C# String formatting:
The DateTime object can output in different formats using the .ToString() function.
Please see the following links
Custom Date and Time Format Strings
DateTime.ToString Method
So, for example:
DateTime.Now.ToString("dd/MM/yyyy h:mm:ss");
That will output in the format you have in your question.
I think your issue is related to the Set language setting in sql.
Similar to this question: SQL Server ISDATE() Function - Can someone explain this?
Can you try to set your sql language to match your format?
Most of the SQL datetime formats should be recognizable by C# DateTime.Parse(youSQLDatetimeVariable). I find it a bit odd what's happening in your case.
Like other said you really shouldn't but here is how you can convert DateTime to various formats:
SELECT Convert(VARCHAR, MyDateTimeField, 112) from MyTable
That number (112 ) indicates the DateTime format that will appear as Varchar
All formats can be found here in details:
http://anubhavg.wordpress.com/2009/06/11/how-to-format-datetime-date-in-sql-server-2005/
Or within your C# code with
YourDatetimeVariable.ToString("MM-dd-yyyy")
Or whatever format you want within those quotes where MM- month number, dd - day number, yyyy - year.

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