one click add blank record

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C#

C#4.0

Dear sir,
when was clicking edit link button there is one more blank record added to the grid please correct me.

The code is:

private void Binddata()
    {
        string selectSQL = "SELECT * FROM reservation";
        ocon.Open();
        SqlCommand cmd = new SqlCommand(selectSQL, ocon);
        SqlDataAdapter adapter = new SqlDataAdapter(cmd);
        DataSet ds = new DataSet();

        adapter.Fill(ds, "reservation");
        ocon.Close();
        gvreservation.DataSource = ds;
        gvreservation.DataBind();
    }

    protected void gvreservation_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        string id = ((TextBox)gvreservation.FooterRow.FindControl("txtFCustomerID")).Text;
        string name = ((TextBox)gvreservation.FooterRow.FindControl("txtFCustomerName")).Text;
        string age = ((TextBox)gvreservation.FooterRow.FindControl("txtFAge")).Text;
        string location = ((DropDownList)gvreservation.FooterRow.FindControl("ddlFLocation")).Text;
        string class1 = ((DropDownList)gvreservation.FooterRow.FindControl("ddlFClass")).Text;
        ocon.Open();
        string sqlstatement ="Insert into reservation(CustomerID,CustomerName,Age,Location,Class)values(@CustomerID,@CustomerName,@Age,@Location,@Class)";
        SqlCommand cmd = new SqlCommand(sqlstatement,ocon);
        cmd.Parameters.Add("@CustomerID",id);
        cmd.Parameters.Add("@CustomerName",name);
        cmd.Parameters.Add("@Age",age);
        cmd.Parameters.Add("@Location",location);
        cmd.Parameters.Add("@Class",class1);
        cmd.ExecuteNonQuery();
        ocon.Close();
        Binddata();
    }

    protected void gvreservation_RowEditing(object sender, GridViewEditEventArgs e)
    {
        string id = ((TextBox)gvreservation.FooterRow.FindControl("txtFCustomerID")).Text;
        string name = ((TextBox)gvreservation.FooterRow.FindControl("txtFCustomerName")).Text;
        string age = ((TextBox)gvreservation.FooterRow.FindControl("txtFAge")).Text;
        string location = ((DropDownList)gvreservation.FooterRow.FindControl("ddlFLocation")).Text;
        string class1 = ((DropDownList)gvreservation.FooterRow.FindControl("ddlFClass")).Text;
        string sqlstatements = "update reservation set CustomerName='"+name+"',Age='"+age+"',Location='"+location+"',Class='"+class1+"' where CustomerID='"+id+"'";
        ocon.Open();
        SqlCommand cmd = new SqlCommand(sqlstatements,ocon);
        cmd.Parameters.Add("@CustomerID",id);
        cmd.Parameters.Add("@CustomerName",name);
        cmd.Parameters.Add("@Age",age);
        cmd.Parameters.Add("@Location",location);
        cmd.Parameters.Add("@Class",class1);
        cmd.ExecuteNonQuery();
        ocon.Close();
        Binddata();
    }

    protected void gvreservation_RowDeleting(object sender, GridViewDeleteEventArgs e)
    {
        string id = ((TextBox)gvreservation.FooterRow.FindControl("txtFCustomerID")).Text;
        string sqlstatement = "Delete from reservation where CustomerID=@CustomerID";
        ocon.Open();
        SqlCommand cmd = new SqlCommand(sqlstatement,ocon);
        cmd.Parameters.Add("@CustomerID",id);
        cmd.ExecuteNonQuery();
        ocon.Close();
        Binddata();
    }
}