Question

In Microsoft SQL Server Management Studio, after calling the stored procedure, I can see that the time has the format 2011-05-20 19:56:09 in table.

However, in my C# program, after using an OdbcConnection to get the record from the table, I find that the time is in the format 05/20/2011 19:56:09. So I manually convert the format MM/DD/YYYY hh:mm:ss to YYYY-MM-DD hh:mm:ss (Actually, how do I verify the format is h or HH since the hour shown is 19?).

My question is why and in which part of connection, the format is changed? How can I set invarient culture in my connection?

cmd = new OdbcCommand("{?=CALL stored_procedure_in_SQL(?,?)}", m_SqlConn);
cmd.Parameters.Add(new OdbcParameter("RETURN_VALUE", OdbcType.Int, 4,
    ParameterDirection.ReturnValue, false, 0, 0, null, 
    DataRowVersion.Default, null));

//@parameter1
cmd.Parameters.Add("@parameter1", OdbcType.VarChar, 50).Value = value1;

//@parameter2
cmd.Parameters.Add("@parameter2", OdbcType.Int)=value2;

object objTime=ds.Tables[0].Rows[0][0]
Console.WriteLine(objTime.Tostring()) //05/20/2011 19:56:09
DateTime dateTime = Cdate(objTime, "MM/dd/yyyy h:mm:ss tt"); 
//2011-05-20 19:56:09 
Console.WriteLine(dateTime.ToString("yyyy-MM-dd HH:mm:ss")); 

//Function Cdate
static public DateTime Cdate(object val, string format)
{
    // check if the object is a date time alread
    string str;
    if(val is DateTime)
    {
        // Since val is already a dateTime,Return here
        return (DateTime)val; 
    }

    // convert via string
    if(val != DBNull.Value)
    {
        str = val.ToString().Trim();
    }
    else
    {
        str = "";
    }

    if(str == "")
    {
        return DateTime.MinValue;
    }
    else
    {
        return DateTime.ParseExact(str, format, 
            CultureInfo.InvariantCulture);
    }
}

Answer 1

You can’t set a DateTime format on a connection string.

What you are seeing are simply different formattings of a certain (internal) representation of DateTime.

The formatting is determined by the tools you use and for .NET code the culture your logged in with.

When you want to display the time, then you need to format, though when using a custom format string like you have, there are no CultureInfo elements involved.

Check the different ToString overloads on DateTime.