.net 将分页展示的GridView的全部数据 导出excel

cs代码如下：

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.OracleClient;
using System.Configuration;
using System.IO;
using System.Text;

public partial class NewFrameWorkUI_Web_UI_Bad_Event_Drug_Bad_Reaction_Bad_Reaction_List : System.Web.UI.Page
{
    OracleConnection StrConn = new OracleConnection(ConfigurationManager.ConnectionStrings["ConnectionStringOracle10"].ConnectionString);
    public string sqlstr; //查询条件sql语句
    public string flag ;//是否分页标志  0 ：分页   1：不分页
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            ViewState["sqlstr"] = "";
            ViewState["flag"] = "0";//初始化为分页
            Get_Data();
            Show_Report_Type();
            this.DropDownList1.Items.Insert(0, "--请选择--");
        }
    }
    public void Show_Report_Type()
    {
        string Str = " select * from drug_bad_dict where status='2' order by id   ";
        OracleDataAdapter da = new OracleDataAdapter(Str, StrConn);
        DataSet ds = new DataSet();
        da.Fill(ds, "Bad");
        this.DropDownList1.DataSource = ds.Tables["Bad"];
        this.DropDownList1.DataTextField = "name";
        this.DropDownList1.DataValueField = "id";
        this.DropDownList1.DataBind();
    }

    public void Get_Data()
    {
        StrConn.Open();
        string str = "select a.*,b.*,d.*,e.*,c.Name as report_name from DRUG_BAD_MASTER a inner join pat_master_index b on a.patient_id=b.patient_id left join DRUG_BAD_dict c on a.report_type=c.id  inner join DRUG_BAD_GUOCHENG d on a.bid = d.bid inner join DRUG_BAD_DETAIL e on a.bid=e.bid   where 1=1 " + (string )ViewState["sqlstr"] + "  order by a.REPORT_DATE desc";

        OracleDataAdapter da = new OracleDataAdapter(str, StrConn);
        DataSet ds = new DataSet();
        da.Fill(ds, "Bad");
        this.SearchGrird.DataSource = ds.Tables["Bad"];
        this.SearchGrird.DataBind();
        StrConn.Close();
        AspNetPager1.RecordCount = ds.Tables["Bad"].Rows.Count;
        PagedDataSource pds = new PagedDataSource();
        pds.DataSource = ds.Tables["Bad"].DefaultView;
        if ((string)ViewState["flag"] == "0")
        {
            pds.AllowPaging = true;
        }
        else
        {
            pds.AllowPaging = false;
        }
        pds.CurrentPageIndex = AspNetPager1.CurrentPageIndex - 1;
        pds.PageSize = AspNetPager1.PageSize;
        SearchGrird.DataSource = pds;
        SearchGrird.DataBind();

    }
    protected void gv_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        int i;
        //执行循环，保证每条数据都可以更新
        for (i = 0; i < SearchGrird.Rows.Count; i++)
        {
            //首先判断是否是数据行
            if (e.Row.RowType == DataControlRowType.DataRow)
            {
                //当鼠标停留时更改背景色
                e.Row.Attributes.Add("onmouseover", "c=this.style.backgroundColor;this.style.backgroundColor='#EDF4FC'");
                //当鼠标移开时还原背景色
                e.Row.Attributes.Add("onmouseout", "this.style.backgroundColor=c");
            }
        }
    }
    protected void gv_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        this.SearchGrird.PageIndex = e.NewPageIndex;
        Get_Data();

    }
    protected void gv_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        if (e.CommandName == "del")
        {
            string str_del1 = "delete from DRUG_BAD_Detail where bid=" + e.CommandArgument.ToString() + "";

            string str_del2 = "delete from DRUG_BAD_MASTER where bid=" + e.CommandArgument.ToString() + "";
            DbHelperOralce.ExecuteSql(str_del1);
            DbHelperOralce.ExecuteSql(str_del2);
            Jscript.Alert("删除成功!");
        }
        Get_Data();
    }
    protected void SearchGrird_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        Sys_Commn.ShowRow(this.SearchGrird, e, "Default");//绑定行样式
    }
    protected void AspNetPager1_PageChanged(object sender, EventArgs e)
    {
        Get_Data();
    }


    protected void btn_Search_Click(object sender, EventArgs e)
    {
        string strsqling = "";
        if (this.TB_Name.Text.Trim() != "")
        {
            strsqling += " and b.name like '%" + this.TB_Name.Text.Trim() + "%'";
        }
        if (this.TB_Start.Text.Trim() != "" && this.TB_End.Text.Trim() != "")
        {
            strsqling += " and ( a.REPORT_DATE  between to_date('" + this.TB_Start.Text.Trim() + "','yyyy-mm-dd') and to_date('" + this.TB_End.Text.Trim() + "','yyyy-mm-dd'))";
        }
        if (this.DropDownList1.SelectedValue != "--请选择--")
        {
            strsqling += " and a.REPORT_TYPE='" + this.DropDownList1.SelectedValue + "'";
        }
        ViewState["sqlstr"] = strsqling;
        Get_Data();
    }

    protected void CreateExcel(object sender, EventArgs e)
    {
        ViewState["flag"] = "1";//不分页
        Get_Data();
        Export("application/ms-excel", "不良反应报告登记表.xls");
        ViewState["flag"] = "0";//分页
    }
    private void Export(string FileType, string FileName)
    {
        Response.Charset = "GB2312";
        Response.ContentEncoding = System.Text.Encoding.UTF8;
        Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(FileName, Encoding.UTF8).ToString());
        Response.ContentType = FileType;
        this.EnableViewState = false;
        StringWriter tw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(tw);
        SearchGrird.RenderControl(hw);
        Response.Write(tw.ToString());
        Response.End();
    }

    ////<summary>
    ////这个方法必须重写，否则出错
    ////</summary>
    ////<param name="control"></param>
    public override void VerifyRenderingInServerForm(Control control)
    {
    }
}