I am using load() method to read data from Excel document to DataTable. I am constructing the DataTable based on the column values.
The issue is for Date columns the WorkSheetCell object shows value of '39815' for date value of '1/2/2009'
How to resolve this issue?
Infragistics.Excel.Workbook wk = Infragistics.Excel.Workbook.Load(openFile.FileName); foreach (Infragistics.Excel.WorksheetRow wkRow in wk.WindowOptions.SelectedWorksheet.Rows) { foreach (Infragistics.Excel.WorksheetCell wkCell in wkRow.Cells)
This probably isn't really an Infragistics issue. If you consider that by default Excel stores its date time values in serial date format you would expect to receive these same values back when not looking at the date in Excel's formatted view.
As you probably know Excel uses the 1900 date system in which the date 1/1/1900 is considered 1, the date 1/2/1900 is considered 2 and so on. The Excel time model is very similar in that it uses numeric values to represent the time of day. Time in Excel is represented as a decimal value. This works alongside the date model so that the date and time values can be combined to create a single value that represents a specific date and time. So for example 1/1/1900 6:00 PM would be represented as 1.75 (the 0.75 time value representing 75% of a day or 24 hours * 0.75).
What I would do to convert these values is simply create a new DateTime variable and set its initial value to the date 1/1/1900. The DateTime type has a method called AddDays which works in the same way as Excel in that it will take the whole number as the number of days and the decimal values to represent the time. After initializing your DateTime variable with the date of 1/1/1900 the AddDays method will return a new DateTime that is adjusted for the value stored by Excel.
As far as converting an Excel worksheet into a data table I don't know a single method calls that can be used to do this. So by default I would simply write my own little conversion function that would take care of this for me and even possibly make it an extension method.
Here is a web link of such a function that someone else wrote: http://www.aspspider.com/resources/Resource510.aspx
Stragely, the answer that Steve wrote, for me returns a day 2 days more then the actual date in the spreadsheet.
I figured out, that you should either set the initial DateTime to 12/31/1899., or add 1 day less, since we are adding up the days from "day 0".
But I still don't know where the other extra day is coming from...
I experienced the same thing and made the change that dargzero described. I also subtracted 1 more for the other additional day.
Another anomoly is that the underlying formats in Excel are also different to VB.Net. I need to format a column name in a datatable to be the same as the date. In excel the cell format was mmm-yy and I needed MMM-yy so I used the following to change that:
For Each myCell In myworksheet.Rows(1).Cells
Dim myDate As DateTime = #12/31/1889 12:00:00 PM#
Dim myDateString As String
' Default to MMM-yy
Dim myFormat As String = "MMM-yy"
' Get the format of the cell for the Column name formatIf myCell.ColumnIndex = 11 Then
myFormat = myCell.CellFormat.FormatString
' Replace the m for minute with the M for month myFormat = myFormat.Replace(
"m", "M")
End If
If myCell.ColumnIndex > 10 And (Not myCell.Value Is Nothing And myCell.Value.ToString().Length > 0) Then
myDate = myDate.AddDays(myCell.Value)
myDateString = myDate.ToString(myFormat)
myTable.Columns.Add(
New DataColumn(myDateString))
This happens on some browsers. Not sure why.
In the future you can surround code in a code tag to format it better.
by the way, I've no idea where all the extra line spaces came from in the code - sorry about that as it looks really messy