如何从当前选定的网格中获取数据

Question

我在grid页面中关注了.aspx。

我需要做什么： 当用户点击它时，应从特定行获取Company Name Product Name No. of records并运行以下过程并下载excel文件。

以下是我的代码：

存储过程：

CREATE proc [dbo].[proc_getHistoryProduct]    
(    
@CompName nvarchar(max) = '',    
@ProdName nvarchar(max) = '',  
@noOfRecords int
)    
as    
begin    
if @ProdName = '' and @CompName = 'NULL'
begin  
select TOP (@noOfRecords) * from ProductDetail where (Product_Description like '%' +    @ProdName + '%' )
end  
else if @CompName = '' and @ProdName = 'NULL'
begin  
select  TOP (@noOfRecords) * from ProductDetail where (Shipper_Name like '%' + @CompName + '%' )
end  
end

要在Excel中下载的代码：

       protected void GridView_SelectedIndexChanged(object sender, EventArgs e)
       {
        GridViewRow row = GridData.SelectedRow;
        int noOfRecords = Convert.ToInt32(row.Cells[3].Text);
        string CompName = row.Cells[2].Text;
        string ProdName = row.Cells[1].Text;
        DataTable dt = (DataTable)Session["UserHistoryProduct"];
        con.Open();
        SqlCommand cmd = new SqlCommand("proc_getHistoryProduct", con);

        cmd.Parameters.Add("@CompName", SqlDbType.VarChar, 1000).Value = CompName;
        cmd.Parameters.Add("@ProdName", SqlDbType.VarChar, 1000).Value = ProdName;
        cmd.Parameters.Add("@noOfRecords", SqlDbType.Int).Value = noOfRecords;
        cmd.CommandType = CommandType.StoredProcedure;
        SqlDataReader dr = cmd.ExecuteReader();

        dt.Load(dr);
        dr.Close();
        con.Close();
        Session["UserHistoryProduct"] = dt;

        DataTable Searchtable = (DataTable)Session["UserHistoryProduct"];

        ExportToExcel(dt);
    }

有谁能告诉我哪里出错了？

编辑：

   public void ExportToExcel(DataTable dt)
      {
        if (dt.Rows.Count > 0)
        {
            string filename = "HistoryProductDetail.xls";
            System.IO.StringWriter tw = new System.IO.StringWriter();
            System.Web.UI.HtmlTextWriter hw = new System.Web.UI.HtmlTextWriter(tw);
            GridView dgGrid = new GridView();
            dgGrid.DataSource = dt;
            dgGrid.DataBind();

            //Get the HTML for the control.
            dgGrid.RenderControl(hw);
            //Write the HTML back to the browser.
            //Response.ContentType = application/vnd.ms-excel;
            Response.ContentType = "application/vnd.ms-excel";
            Response.AppendHeader("Content-Disposition", "attachment; filename=" + filename + "");
            this.EnableViewState = false;
            Response.Write(tw.ToString());
            Response.End();
        }
    }

Answer 1

尝试使用SqlDataAdapter

    SqlDataAdapter adp = new SqlDataAdapter(cmd);
    adp.Fill(dt);

而不是SqlDataReader

    SqlDataReader dr = cmd.ExecuteReader();
    dt.Load(dr);
    dr.Close();

我不确定，但可能有所帮助

Answer 2

终于解决了我的问题！

我需要做的是甚至在OnClick="DownloadExcel_Click"即<asp:LinkButton>

上致电Download

public void DownloadExcel_Click(object sender, EventArgs e)
    {
        var downloadLink = (Control)sender;
        GridViewRow row = (GridViewRow)downloadLink.NamingContainer;
        Label lblProduct = (Label)row.FindControl("lblprodname");
        string prodName = lblProduct.Text;
        Label lblCompany = (Label)row.FindControl("lblcompname");
        string compName = lblCompany.Text;
        Label lblRecords  = (Label)row.FindControl("lblrecords");
        int noOfRecords = Convert.ToInt32(lblRecords.Text);

        DataTable dt = (DataTable)Session["UserHistoryProduct"];
        con.Open();
        SqlCommand cmd = new SqlCommand("proc_getProductHistory", con);

            cmd.Parameters.Add("@ProdName", SqlDbType.VarChar, 1000).Value = prodName;
            cmd.Parameters.Add("@CompName", SqlDbType.VarChar, 1000).Value = compName;
            cmd.Parameters.Add("@noOfRecords", SqlDbType.Int).Value = noOfRecords;
        cmd.CommandType = CommandType.StoredProcedure;
        using (SqlDataAdapter da = new SqlDataAdapter(cmd))
        {
            dt = new DataTable();
            da.Fill(dt);
        }

        //dt.Load(dr);
        //dr.Close();
        con.Close();
        Session["UserHistoryProduct"] = dt;

        //DataTable Searchtable = (DataTable)Session["UserHistoryProduct"];

        ExportToExcel(dt);


    }