I have written the code as below. here problem is that dt
remain null. how to solve thst please tell me.
public partial class Form1 : Form
{
private DataTable DTable;
private DataRow drow;

public Form1()
{
InitializeComponent();
}

private OleDbConnection getConnection()
{
OleDbConnection con=new OleDbConnection
(@"Provider=Microsoft.Jet.OLEDB.4.0;Data
Source=C:\Documents and Settings\Administrator\My
Documents\Visual Studio 2008\Projects\winApp for
Student\winApp for
Student\App_Data\SchooMgnSystem.mdb;Persist Security
Info=True");
return con;
}
private void button1_Click(object sender, EventArgs
e)
{
InsertData();
}

private void InsertData()
{
if (DTable==null)
{
DTable = new DataTable();
DTable.Columns.Add("StudID", typeof(string));
DTable.Columns.Add("StudName", typeof
(string));
DTable.Columns.Add("Address", typeof(string));
drow = DTable.NewRow();
drow[0] = txtStudID.Text;
drow[1] = txtSTudName.Text;
drow[2] = txtAddress.Text;
DTable.Rows.Add(drow);
grdStudent.DataSource = DTable;
}
else
{
drow = DTable.NewRow();
drow[0] = txtStudID.Text;
drow[1] = txtSTudName.Text;
drow[2] = txtAddress.Text;
DTable.Rows.Add(drow);
grdStudent.DataSource = DTable;
}
}

private void button2_Click(object sender, EventArgs
e)
{
string cmdstr;
OleDbCommand cmd;
OleDbConnection con = getConnection();
foreach (DataRow Drow in DTable.Rows)
{
cmdstr = "Insert into Student values('" +
drow[0].ToString() + "','" + drow[1].ToString() + "','"+drow
[2].ToString()+"')";
cmd = new OleDbCommand(cmdstr,con);
try
{
con.Open();
cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
con.Close();
}

}
}