Excel导入/导出

注释很详尽，就不多说了，简单解释下原理：

GetExcelSheet方法：导入功能。原理为把Excel上传至服务器，然后把Excel当作数据库读数据到DataTable返回，然后删除服务器端的Excel，最后对返回的DataTable进行数据处理。

ReportToExcel方法：导出方法一。原理为把控件以Excel的形式输出，但是只支持浏览器下载，因为迅雷识别到的是网页地址，下载到的会是整个网页。

ExportExcel方法：导出方法二。原理为通过com操作Excel，需要引入Excel安装包中的Microsoft.Office.Interop.Excel.dll文件（具体dll文件位置自行百度），并且需要对DCOM进行权限配置（配置方式参考：http://blog.csdn.net/lploveme/article/details/8215265）。优点是稳定性、兼容性好，支持各种方式下载。

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.OleDb;
using System.IO;
using System.Reflection;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Microsoft.Office.Interop.Excel;
using Spring.Context.Support;
using DataTable = System.Data.DataTable;
using Page = System.Web.UI.Page;
using Spring.Context;
using IBLL;
using Model;

namespace Common
{
    public class DataToExcel : System.Web.UI.Page
    {

        #region IBLL层实例
        static IApplicationContext ctx = ContextRegistry.GetContext();
        /// <summary>
        ///   T_DictionaryBLL实例
        /// </summary>
        public static IBLL<T_Dictionary> DictionaryBLL
        {
            get { return ctx.GetObject("T_DictionaryBLL") as IBLL<T_Dictionary>; }
        }
        #endregion IBLL层实例

        /// <summary>
        /// 导入-将Excel中的数据放到DataTable中
        /// </summary>
        /// <param name="page">上传页面</param>
        /// <param name="up">上传控件</param>
        /// <param name="path">上传路径</param>
        /// <param name="table">DataTable表名</param>
        /// <returns></returns>
        public static DataTable GetExcelSheet(Page page, FileUpload up, string path, string table = "ExcelTable")
        {
            //验证文件格式
            string fileType = "xls|xlsx";
            if (!up.HasFile || fileType.IndexOf(Upload.GetExtension(up.FileName)) < 0)
            {
                MessageBox.Show(page, "请上传.xls或.xlsx结尾的Excel文件！", 1);
                return null;
            }
            if (up.FileContent.Length > 1024 * 1024 * 10)
            {
                MessageBox.Show(page, "上传文件不允许超过10M！", 1);
                return null;
            }
            string fileName = DateTime.Now.ToString("yyyyMMddHHmmssffff") + up.FileName;//文件名称
            string fullUrl = page.Server.MapPath(path);//物理路径

            if (!Directory.Exists(fullUrl))
            {
                Directory.CreateDirectory(fullUrl); //如果不存在，则创建
            }
            string webFilePath = fullUrl + "//" + fileName; // 服务器端文件路径   
            up.SaveAs(webFilePath);

            //office2007之前 仅支持.xls
            //const string cmdText = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0};Extended Properties='Excel 8.0;IMEX=1';";
            //支持.xls和.xlsx，即包括office2010等版本的   HDR=Yes代表第一行是标题，不是数据；
            string cmdText = ConfigurationManager.AppSettings["excelType"].ToString();

            DataTable dt = null;
            //建立连接
            OleDbConnection conn = new OleDbConnection(string.Format(cmdText, webFilePath));
            try
            {
                //打开连接
                if (conn.State == ConnectionState.Broken || conn.State == ConnectionState.Closed)
                {
                    conn.Open();
                }

                DataTable schemaTable = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                //获取Excel的第一个Sheet名称
                string sheetName = schemaTable.Rows[0]["TABLE_NAME"].ToString().Trim();

                //查询sheet中的数据
                string strSql = "select * from [" + sheetName + "]";
                OleDbDataAdapter da = new OleDbDataAdapter(strSql, conn);
                DataSet ds = new DataSet();
                da.Fill(ds, table);
                dt = ds.Tables[0];
                return dt;
            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                conn.Close();
                conn.Dispose();
                //删除文件
                Upload upload = new Upload();
                upload.DeleteImg(path + fileName);
            }
        }

        /// <summary>
        /// 导出Excel，此方法较简单，但是不支持迅雷等下载工具，只能浏览器下载
        /// </summary>
        /// <param name="control">导出控件</param>
        /// <param name="name">导出文件名字</param>
        /// /// <param name="name">表头</param>
        public static void ReportToExcel(System.Web.UI.Control control, string name, string head)
        {
            //HttpContext.Current.Response.Buffer = true;
            HttpContext.Current.Response.Charset = "utf-8";
            HttpContext.Current.Response.AppendHeader("Content-Disposition", "attachment;filename=" + HttpUtility.UrlEncode(name, System.Text.Encoding.UTF8) + ".xls");
            HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
            HttpContext.Current.Response.ContentType = "application/ms-excel";
            control.EnableViewState = false;
            StringWriter oStringWriter = new StringWriter();
            HtmlTextWriter oHtmlTextWriter = new HtmlTextWriter(oStringWriter);
            control.RenderControl(oHtmlTextWriter);
            StringBuilder table = new StringBuilder("<html><head><meta http-equiv=Content-Type content=\"text/html; charset=GB2312 \"><title>Copyright by SDU</title></head><body>");
            table.Append(head);
            table.Append(oStringWriter.ToString());
            table.Append("</table></body></html>");
            while (table.ToString().Contains("<td class=\"text-center\""))
            {
                int start = table.ToString().IndexOf("<td class=\"text-center\"");
                int count = table.ToString().IndexOf("</td>", start) + 5 - start;
                table.Remove(start, count);
            }
            HttpContext.Current.Response.Clear();
            HttpContext.Current.Response.Write(table.ToString());
            HttpContext.Current.Response.End();
        }

        /// <summary>
        /// 导出Excel，此方法虽然复杂，需要服务端配置一下DCOM权限，但是兼容性非常好，支持任何下载
        /// </summary>
        /// <typeparam name="T">要导出的类型</typeparam>
        /// <param name="list">要导出的List</param>
        /// <param name="column">要导出的列</param>
        /// <param name="name">导出文件的名字</param>
        /// <param name="page">操作页面</param>
        /// <param name="path">文件暂存路径</param>
        /// <param name="joinRow">要合并的行及数据</param>
        public static void ExportExcel<T>(List<T> list, Dictionary<string, string> column, Dictionary<string, string> dictionary, string name, Page page, string path, Dictionary<string, string> joinRow= null)
        {            
            string fileName = name+DateTime.Now.ToString("yyyyMMddHHmmssffff") + ".xls"; //文件名称
            string fullUrl = page.Server.MapPath(path); //物理路径
            if (!Directory.Exists(fullUrl))
            {
                Directory.CreateDirectory(fullUrl); //如果不存在，则创建
            }
            //删除2天之前的文件
            ClearDateOutImg(page, path);
            string webFilePath = fullUrl + fileName; // 服务器端文件路径  
            if (File.Exists(webFilePath))
            {
                File.Delete(webFilePath);
            }

            object Nothing = System.Reflection.Missing.Value; //定义Nothing
            Application excleApp = new ApplicationClass(); //创建Excel应用程序对象的一个实例，相当于我们从开始菜单打开Excel应用程序，对excleApp进行初始化
            Workbook excleWork = excleApp.Workbooks.Add(Nothing); //exclework，对exclework进行初始化
            Worksheet ws = (Worksheet)excleWork.Worksheets[1]; //定义ws为工作文档中的第一个sheet
            int i = 1;
            //设置列名
            foreach (KeyValuePair<string, string> pair in column)
            {
                ws.Cells[1, i++] = pair.Value;
            }
            //获取合并列起始位置
            int j = i;
            //设置合并的列名及值 
            if (joinRow != null)
            {
                foreach (KeyValuePair<string, string> pair in joinRow)
                {
                    ws.Cells[1, i] = pair.Key;
                    ws.Cells[2, i++] = pair.Value;
                }
            }

            for (int r = 0; r < list.Count; r++)
            {
                Type type = list[r].GetType(); //获取类型
                int c = 1;
                foreach (KeyValuePair<string, string> pair in column)
                {
                    System.Reflection.PropertyInfo propertyInfo = type.GetProperty(pair.Key); //获取指定名称的属性
                    string value =  propertyInfo.GetValue(list[r], null).ToString(); //获取属性值
                    //转换数据字典
                    foreach (KeyValuePair<string, string> dPair in dictionary)
                    {
                        if (pair.Key == dPair.Key)
                        {
                            value = DictionaryBLL.GetName(dPair.Value, propertyInfo.GetValue(list[r], null).ToString());
                        }
                    }
                    ws.Cells[r + 2, c++] = value;
                }
            }

            //合并单元格
            while (i>j)
            {
               Range rangeProgram = ws.get_Range(ws.Cells[2,j], ws.Cells[list.Count+1,j]);//获取需要合并的单元格的范围
                rangeProgram.Application.DisplayAlerts = false;
                rangeProgram.Merge(Missing.Value);
                rangeProgram.Application.DisplayAlerts = true;
                j++;
            }

            #region 填充Excel图标

            /*
            Range range1 = ws.get_Range("A1", "A1");//选定（A1,A1）这个单元格
            range1.Value2 = "3";//对这个单元格进行填充内容
            range1 = ws.get_Range("A2", "A2");//同上
            range1.Value2 = "5.7";//同上
            range1 = ws.get_Range("A3", "A3");//同上
            range1.Value2 = "4.8";//同上
            range1 = ws.get_Range("A4", "A4");//同上
            range1.Value2 = "9.2";//同上
            range1 = ws.get_Range("A5", "A5");//同上
            range1.Value2 = "6.4";//同上
            excleWork.Charts.Add(Nothing, Nothing, Nothing, Nothing);//添加一个图表
            excleWork.ActiveChart.ChartType = XlChartType.xl3DColumnClustered;//设置图表的类型是三维柱状图
            excleWork.ActiveChart.SetSourceData(ws.get_Range("A1", "A5"), XlRowCol.xlColumns);//设置这个三维柱状图的数据源
            excleWork.ActiveChart.Location(XlChartLocation.xlLocationAsObject, "sheet1");//设置你要将这个柱状图添加到什么地方
            excleWork.ActiveChart.HasTitle = true;//设置柱状图是否有标题
            excleWork.ActiveChart.ChartTitle.Text = "创建图表";//设置标题的内容为“创建图表”
            excleWork.ActiveChart.HasDataTable = false;//设置柱状图是否有数据表
            */

            #endregion 填充Excel图标
            try
            {

                excleWork.SaveAs(webFilePath, Nothing, Nothing, Nothing, Nothing, Nothing, XlSaveAsAccessMode.xlExclusive,
                    Nothing, Nothing, Nothing, Nothing, Nothing); //保存动态生成的excle表
                //释放资源
                excleApp.Application.Quit();
                if (excleApp != null)
                {
                    excleApp = null;
                }
                MessageBox.ShowAndRedirectParent(page, "导出成功！", 4, path + fileName);

            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
        ///   <summary>      
        ///   删除过期的文件。       
        ///  </summary>       
        private static void ClearDateOutImg(Page page, string path)
        {
            //先取得文件夹中的文件列表          
            string[] fileEntries = System.IO.Directory.GetFiles(page.Server.MapPath(path));
            foreach (string singFiles in fileEntries)//遍历文件列表           
            {
                //将文件的生成日期与系统日期相比，如果是2天以前生成的文件，删除它               
                if (
                    System.DateTime.Compare(System.IO.File.GetCreationTime(singFiles).AddDays(2), System.DateTime.Now) <
                    0)
                {
                    System.IO.File.Delete(singFiles);
                }
            }
        }

    }
}