C# not reading excel date from spreadsheet

Question

I uploaded an excel spreadsheet using Microsoft.Office.Interop.Excel. When I try to read cells with a date value in order to insert it into my data set, its not being recognized as a date and it comes up as a random number? this is the way that I refer to the cell:

Excel.Range startDate = objsheet.get_Range("C1:C" + lastUsedRow, System.Type.Missing);
double dbl = Convert.ToDouble(startDate);
DateTime conv = DateTime.FromOADate(dbl);
(row[3] = ((Microsoft.Office.Interop.Excel.Range)objsheet.Cells[rowIndex, 4]).Value2;)

Answer 1

From https://stackoverflow.com/a/4538367/1397117

You need to convert the date format from OLE Automation to the .net format by using DateTime.FromOADate.

double d = double.Parse(b);  
DateTime conv = DateTime.FromOADate(d);

And I echo suggestions below that answer to use .Value instead of .Value2.

Answer 2

row[3] = Convert.ToDateTime(((Microsoft.Office.Interop.Excel.Range)objsheet.Cells[rowIndex, 4]).Value2.ToString());

May do it for you, see this link.

Answer 3

In my project when I had to read data from excel, I created a method which takes cell text as input and C# DateTime as output.

public DateTime ReadDateFromExcel(string dateFromXL)
{
    Regex dateRegex = new Regex("^([1-9]|0[1-9]|1[0-2])[- / .]([1-9]|0[1-9]|1[0-9]|2[0-9]|3[0-1])[- / .](1[9][0-9][0-9]|2[0][0-9][0-9])$");
    DateTime dtParam = new DateTime();            
    if (!DateTime.TryParse(dateFromXL, out dtParam))
    {
        double oaDate = 0;
        if (Double.TryParse(dateFromXL, out oaDate))
        {
            dateFromXL = DateTime.FromOADate(oaDate).ToString("MM/dd/yyyy");
            if (!dateRegex.IsMatch(dateFromXL))
            {
                Console.Writeline("Date not in correct format");
            }
            else
            {
                dtParam = readDateFromExcel(dateFromXL);
            }
        }
        else
        {
            Console.Writeline("Date not in correct format");
        }
    }
    else
    {
        Console.Writeline("Date is in correct format");
    }
    return dtParam;
}