working with access database update statment not working

Question

string date=
DateTime.Now.ToString("d.M.yyyy",System.Globalization.DateTimeFormatInfo.InvariantInfo);

String MyString = @"UPDATE cas SET Odhod= '" + label1.Text + "' 
WHERE sifra = " + textBox1.Text + " and Datum = "+date+"";

When I do thise update without Datum it works, but with Datum doesn't work. I'm connected to accesss database, and Datum field type in table is date/time Guys please help.

Hire is the program: https://www.dropbox.com/s/hx4zduvul8mh2uy/8.4.zip

Pictre of problem: http://img43.imageshack.us/img43/5189/errorbh.jpg

Answer 1

As usual, using string concatenation brings in a lot of trouble.
(Sql Injection, Parsing problems)

Just use parametrized queries

string MyString = @"UPDATE cas SET Odhod= ? WHERE sifra = ? and Datum = ?"; 


using(OleDbConnection cn = new OleDbConnection(connectionstring))
using(OleDbCommand cmd = new OleDbCommand(MyString, cn)
{
    cn.Open();
    cmd.Parameters.AddWithValue("@p1", label1.Text);
    cmd.Parameters.AddWithValue("@p2", textbox.Text);
    cmd.Parameters.AddWithValue("@p3", Convert.ToDate(date));
    cmd.ExecuteNonQuery();
}

Of course, the Date value stored in the Datum field should be exactly like the date passed in parameter @p3. Sometime it is good to add also the time value to your date

string date= DateTime.Now.ToString("d.M.yyyy 00:00:00", ......);