1、Excel数据导入到数据库中:
在页面放置1个按钮控件(Button1)和1个文件上传控件(FileUpload1)»更多DevExpress开发资源与帮助文档
   protected void Page_Load(object sender, EventArgs e)
   {
       GridView1.Visible = false;
   }
   protected void Button1_Click(object sender, EventArgs e)
   {

       try
       {
           if (FileUpload1.PostedFile.FileName != "")
           {
               string filepath = FileUpload1.PostedFile.FileName;
               string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
               string sheetname = "Sheet1";
               string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + filepath + ";Extended Properties=Excel 8.0;";
               OleDbConnection conn = new OleDbConnection(strConn);
               OleDbDataAdapter oada = new OleDbDataAdapter("select * from [" + sheetname + "$]", conn);
               DataSet ds = new DataSet();
               oada.Fill(ds);
               GridView1.DataSource = ds;
               GridView1.DataBind();
               GridView1.Visible = true;
           }
       }
       catch (Exception error)
       {
           this.Label1.Text = "上传发生错误!原因:" + error.ToString();
       }
   }

注意把Excel文件属性中加入ASPNET用户权限,不然不能导入

3、将数据库中的数据导入Excel中,在这里我讲叙自己实践中的两个方法:

方法一:从最基本的写文件入手,将从数据库中读出来的数据写入到Excel中;

//该方法实现将数据导入到Excel文件中,其中的DataTable dt就是你需要将数据写入到Excel中的数据;
public void ExportExcel( DataTable dt , StreamWriter w )
...{
   try
   ...{
       for( int i = 0 ; i < dt.Columns.Count ; i ++ )
       ...{
            w.Write ( dt.Columns[i] );
            w.Write( ' ' );
        }
        w.Write ( " " );

       object[] values = new object [dt.Columns.Count];
       foreach ( DataRow dr in dt.Rows )
       ...{
            values = dr.ItemArray ;
           for ( int i = 0 ; i < dt.Columns.Count ; i++ )
           ...{
                w.Write ( values[i] );
                w.Write ( ' ' );
            }
            w.Write ( " " );
        }
        w.Flush();
        w.Close();
    }
   catch
   ...{
        w.Close();
    }
}

StreamWriter w就是你自己创建的一个流,创建该数据流时,你需要自己指定需要将数据写入到那个文件,即指定文件路径,要实现下载的话,就可以简单的用Response.Redirect

( "指定需要被下载的文件路径" );

方法二:该方法实现的是将数据从DataGrid中导入到Excel中:

//filename为Excel的名字,ToExcelGrid就是数据源,在此为DataGrid数据源;
private void ExportExcelFromDataGrid( string filename , System.Web.UI.WebControls.DataGrid ToExcelGrid )
...{
    Response.Clear();
    Response.Buffer= true;    
    Response.Charset="utf-8";          
    Response.AppendHeader("Content-Disposition","p_w_upload;filename="+Server.UrlEncode ( filename ) );    
    Response.ContentEncoding=System.Text.Encoding.GetEncoding("utf-8");//设置输出流为简体中文  
    Response.ContentType = "application/ms-excel";//设置输出文件类型为excel文件。    
   this.EnableViewState = false;          
    System.Globalization.CultureInfo myCItrad = new System.Globalization.CultureInfo("ZH-CN",true);  
    System.IO.StringWriter oStringWriter = new System.IO.StringWriter(myCItrad);    
    System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);  
    ToExcelGrid.RenderControl(oHtmlTextWriter);    
    Response.Write(oStringWriter.ToString());  
    Response.End();

Excel导出:
页面上放一个GridView控件,ID为GridView1,添加个导出按钮ID为Button2

   protected void Button2_Click(object sender, EventArgs e)
   {
       Response.Clear();
       Response.Buffer = true;
       Response.Charset = "GB2312";
       Response.AppendHeader("Content-Disposition", "p_w_upload;filename=FileName.xls");
       // 如果设置为 GetEncoding("GB2312");导出的文件将会出现乱码!!!
       Response.ContentEncoding = System.Text.Encoding.UTF7;
       Response.ContentType = "application/ms-excel";//设置输出文件类型为excel文件。
       System.IO.StringWriter oStringWriter = new System.IO.StringWriter();
       System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
       this.GridView1.RenderControl(oHtmlTextWriter);
       Response.Output.Write(oStringWriter.ToString());
       Response.Flush();
       Response.End();

   }

页面后台必须重写这两个方法,不然出现错误!
   public override void VerifyRenderingInServerForm( Control control )
   {

   }
   protected override void Render(HtmlTextWriter writer)
   {
       if (Page != null)
       {
           Page.VerifyRenderingInServerForm(this);
       }
       base.Render(writer);
   }

将GridView打印出来,添加个打印按钮,ID为Button4
   protected void Button4_Click(object sender, EventArgs e)
   {
       Response.Write("<script> window.print()</script>");
   }