该如何回滚？

[bengdeng]

我是个初学者，以下是我的代码：

------翻页------
protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView1.PageIndex = e.NewPageIndex;
delete();
add();
lb1.Text = tibaoje();
float a1 = float.Parse(lb1.Text.Trim());
float b1 = float.Parse(lb2.Text.Trim());
if (a1 > b1)
{
Page.RegisterStartupScript("", "<script language='javascript'>window.alert('请重新填写！');</script>");
}
bind1();
}
}

private string tibaoje() //计算提报金额
{

string sqlstr5 = "select sum(amount*price) from material,tibaoxj where tibaoxj.wl_num=material.wl_num and tibaoxj.tb_num=@tb_num";

mycmd = new SqlCommand(sqlstr5, con);
con.Open();
mycmd.Parameters.Add("@tb_num", SqlDbType.Char).Value = (string)Session["tb_num"];
string tbcash = mycmd.ExecuteScalar().ToString();
con.Close();
return tbcash;

}

-------增加记录操作-------
private void add()
{
int n = GridView1.Rows.Count;
for (int i = 0; i < n; i++)
{
if (((TextBox)(GridView1.Rows[i].Cells[4].FindControl("tb1"))).Text != "")
{
key = GridView1.DataKeys[i].Value.ToString();
mycmd = new SqlCommand("insert into tibaoxj values(@tb_num,@wl_num,@amount)", con);
mycmd.Parameters.Add("@tb_num", SqlDbType.Char).Value = (string)Session["tb_num"];
mycmd.Parameters.Add("@wl_num", SqlDbType.Char).Value = key;
mycmd.Parameters.Add("@amount", SqlDbType.Int).Value = ((TextBox)(GridView1.Rows[i].Cells[4].FindControl("tb1"))).Text;
con.Open();
mycmd.ExecuteNonQuery();
con.Close();
}
}
}

--------删除记录操作-------
private void delete()
{
int n1 = GridView1.Rows.Count;

for (int i = 0; i < n1; i++)
{

key = GridView1.DataKeys[i].Value.ToString();
string sqlstr2 = "select * from tibaoxj where tb_num=@tb_num and wl_num=@wl_num";
myda = new SqlDataAdapter(sqlstr2, con);
DataSet myds1 = new DataSet();
myda.SelectCommand.Parameters.Add("@tb_num", SqlDbType.Char).Value = (string)Session["tb_num"];
myda.SelectCommand.Parameters.Add("@wl_num", SqlDbType.Char).Value = key;
myda.Fill(myds1, "tibao1");
int count1 = myds1.Tables["tibao1"].Rows.Count;
if (count1 != 0)
{

mycmd = new SqlCommand("delete tibaoxj where tb_num=@tb_num and wl_num=@wl_num", con);
mycmd.Parameters.Add("@tb_num", SqlDbType.Char).Value = (string)Session["tb_num"];
mycmd.Parameters.Add("@wl_num", SqlDbType.Char).Value = key;
con.Open();
mycmd.ExecuteNonQuery();
con.Close();

}
}
Gridview最后一列是模版列，输入数量的，翻页时我用最笨的办法：先delete再add，都是用的循环的办法，开始我是这么做的，后来发现不行，其实应该当判断到a1>b1时，除了提示外，应该回到delete之前，不知道应该怎么做呢？

[gaolin]

向楼主致敬！国庆还工作在第一线！

[gaolin]

我也有个最笨的方法，可以在数据库中再增加一列，原来的数据不要删除掉，对于新操作的数据你放到新的列里面，另外还要增加一列控制列（比如暂时填写1，如果需要回去改为2，这样如果用户要取消那就把控制列换为2，这样以后如果新增加的列数据存在且控制列不为2 的话那就以第二列为准否则以原来的为准）