DATAGRIDで入力中のセルのデータをDATASETに反映したい

DataTable t = null;
private void Form1_Load(object sender, System.EventArgs e)
{
    textBox1.Text = "";

    t = new DataTable("Sample");
    t.Columns.Add("Col1",typeof(string));
    t.Columns.Add("Col2",typeof(string));
    t.Columns.Add("Col3",typeof(int));
    int i = 0;
    DataRow r;
    while (i < 20)
    {
        r = t.NewRow();
        r["Col1"] = 5.ToString();
        r["Col2"] = i.ToString();
        r["Col3"] = i * 3;
        t.Rows.Add(r);
        i++;
    }

    DataView dv = new DataView(t);
    dv.AllowNew = false;
    dataGrid1.DataSource = dv;
}

private void textBox1_Enter(object sender, System.EventArgs e)
{
    dataGrid2.DataSource = t;
}