protected void Page_Load(object sender, EventArgs e)
    {
        BindDropList();
        if (!IsPostBack)
        {
            DataTable dt = new DataTable();
            DataColumn dc;
           
            dc = new DataColumn();
            dc.ColumnName = "Name";
            dt.Columns.Add(dc);
            dc = new DataColumn();
            dc.ColumnName = "LName";
            dt.Columns.Add(dc);
            Session["dt"] = dt;
        }
    }
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protected void Button3_Click(object sender, EventArgs e)
    {
        DataTable dt = (DataTable)Session["dt"];
        DataRow dr;
        foreach (GridViewRow row in GridView1.Rows)
        {
            CheckBox ch = (CheckBox)row.FindControl("asd");
            if (ch.Checked==true)           
            {
                try
                {
                            dr = dt.NewRow();
                            dr["Name"] = row.Cells[1].Text;
                            dr["LName"] = row.Cells[2].Text;
                            dt.Rows.Add(dr); 
                   
                }
                catch (Exception ex)
                { Response.Write(ex.Message); }               
            }
        }
        GridView2.DataSource = dt;
        GridView2.DataBind();
    }
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