C#

private void menuItem4_Click(object sender, EventArgs e)        {            
  string wCS = @"Data Source =\Storage Card\ModeDifféré\BaseGmaoLocale.sdf;";            
  SqlCeConnection sqlceconn = new SqlCeConnection(wCS);           
  SqlCeCommand command2 = sqlceconn.CreateCommand();            
  command2.CommandText = "INSERT INTO compteurs2 ([com], [quantite],[datequantite] ) Values(@com,@qtte,SYSDATE)";            
  //command2.ExecuteNonQuery(); -- a little mistake

  SqlCeParameter com = new SqlCeParameter("@com", SqlDbType.NVarChar);            
  com.Value = comComboBox.SelectedItem.ToString();            
  command2.Parameters.Add(com);            
  
  SqlCeParameter qtte = new SqlCeParameter("@qtte", SqlDbType.Float);            
  qtte.Value = float.Parse(textBox1.Text);            
  command2.Parameters.Add(qtte);        

  command2.ExecuteNonQuery();
}

private void menuItem4_Click(object sender, EventArgs e)
        {
            DateTime t = DateTime.Now;
            string wCS = @"Data Source =\Storage Card\ModeDifféré\BaseGmaoLocale.sdf;";
            SqlCeConnection sqlceconn = new SqlCeConnection(wCS);
            SqlCeCommand command2 = sqlceconn.CreateCommand();
            command2.CommandText = "INSERT INTO compteurs2 ([com], [quantite],[datequantite] ) Values(@com,@qtte,@dat)";
            
            //Add the parameters
            SqlCeParameter com = new SqlCeParameter("@com", SqlDbType.NVarChar);
            com.Value = comComboBox.SelectedItem.ToString();

            command2.Parameters.Add(com);
            SqlCeParameter qtte = new SqlCeParameter("@qtte", SqlDbType.Float);
            qtte.Value = float.Parse(textBox1.Text);

            command2.Parameters.Add(com);
            SqlCeParameter dat = new SqlCeParameter("@dat", SqlDbType.Float);
            dat.Value = t;

            command2.Parameters.Add(dat);
            command2.ExecuteNonQuery();
        }

private void menuItem4_Click(object sender, EventArgs e)
{
   // define the connection string
   string wCS = @"Data Source =\Storage Card\ModeDifféré\BaseGmaoLocale.sdf;";
  
   // create a connection - this way it will be disposed and closed at the en of the using block
   using(SqlCeConnection sqlceconn = new SqlCeConnection(wCS))
   {
      // define the insert statement
      string insertString = "INSERT INTO compteurs2 ([com], [quantite],[datequantite] ) Values(@com,@qtte,@dat)";

      // create the command based on the insert string and the connection
      SqlCeCommand command2 = sqlceconn.CreateCommand(insertString, sqlceconn);
      
      // define the parameters
      SqlCeParameter com = new SqlCeParameter("@com", SqlDbType.NVarChar);
      SqlCeParameter qtte = new SqlCeParameter("@qtte", SqlDbType.Float);
      SqlCeParameter dat = new SqlCeParameter("@dat", SqlDbType.DateTime);

      // attach values to these parameters
      com.Value = comComboBox.SelectedItem.ToString();
      qtte.Value = float.Parse(textBox1.Text);
      dat.Value = DateTime.Now;

      // attach the parameters to the command
      command2.Parameters.Add(com);
      command2.Parameters.Add(qtte);
      command2.Parameters.Add(dat);

      // open the conenction
      command2.Connection.Open();
      // execute the insert
      command2.ExecuteNonQuery();
   }
   // note that here the connection is closed
}

SqlCeCommand command2 = sqlceconn.CreateCommand(insertString,sqlceconn);

SqlCeCommand command2 = sqlceconn.CreateCommand();
command2.CommandText = insertString;

SqlCeCommand command2 = new SqlCeCommand(insertString,sqlceconn);

Sr...Frank wrote:

Please let me know right code.

private void button2_Click(object sender, EventArgs e)
        {
            foreach (Form2 f in this.MdiChildren)
            {
                f.Dispose();
            }
        }