DataExport 导出excel类

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;

/// <summary>
/// Summary description for DataExport
/// </summary>
public class DataExport
{
    public DataExport()
    {
        //
        // TODO: Add constructor logic here
        //
    }
    //-----------By Gu Yeqing Added 2007-6-6
    public static void Export(GridView dgExport, DataTable dtData, string name)
    {
        System.Web.HttpContext curContext = System.Web.HttpContext.Current;
        // IO用于导出并返回excel文件
        System.IO.StringWriter strWriter = null;
        System.Web.UI.HtmlTextWriter htmlWriter = null;

        if (dtData != null)
        {
            // 设置编码和附件格式
            curContext.Response.Clear();
            curContext.Response.Buffer = true;
            curContext.Response.ContentType = "application/vnd.ms-excel";
            curContext.Response.ContentEncoding = System.Text.Encoding.GetEncoding("UTF-8");
            curContext.Response.Charset = "GB2312";
            curContext.Response.AppendHeader("content-disposition", "attachment;filename=\"" + System.Web.HttpUtility.UrlEncode(name, System.Text.Encoding.UTF8) + ".xls\"");


            // 导出excel文件
            strWriter = new System.IO.StringWriter();
            htmlWriter = new System.Web.UI.HtmlTextWriter(strWriter);


            dgExport.DataSource = dtData.DefaultView;
            dgExport.DataBind();
            // 返回客户端
            dgExport.RenderControl(htmlWriter);
            curContext.Response.Write(strWriter.ToString());
            curContext.Response.End();
        }
    }

    /// <summary>
    /// 导出到Excel
    /// </summary>
    /// <param name="_caption">表头标题文字，以 | 分隔</param>
    /// <param name="ds"></param>
    /// <param name="ef"></param>
    /// <param name="FileName"></param>
    public static void ExportToExcel(string __strCaption, DataSet __dsSource, ExportFormat __ef, string __strFileName, Page __page)
    {
        string[] s = __strCaption.Trim().Trim('|').Split('|');
        DataTable dt = __dsSource.Tables[0];
        for (int i = 0; i < s.Length; i++)
        {
            if (i < dt.Columns.Count)
                dt.Columns[i].Caption = s[i];
            else
                break;
        }
        ExportToExcel(__dsSource, __ef, __strFileName,__page);
    }


    /// <summary>
    /// 导出到Excel
    /// </summary>
    /// <param name="_caption">表头标题文字</param>
    /// <param name="ds"></param>
    /// <param name="ef"></param>
    /// <param name="FileName"></param>
    public static void ExportToExcel(string[] __strArrCaption, DataSet __dsSource, ExportFormat __ef, string __strFileName,Page __page)
    {
        DataTable dt = __dsSource.Tables[0];
        for (int i = 0; i < __strArrCaption.Length; i++)
        {
            if (i < dt.Columns.Count)
                dt.Columns[i].Caption = __strArrCaption[i];
            else
                break;
        }
        ExportToExcel(__dsSource, __ef, __strFileName, __page);
    }

    /// <summary>
    ///
    /// </summary>
    /// <param name="ds"></param>
    /// <param name="ef"></param>
    /// <param name="FileName"></param>
    public static void ExportToExcel(DataSet __dsSource, ExportFormat __ef, string __strFileName,Page __page)
    {
        try
        {
            __page.Response.Clear();
            __page.Response.Buffer = true;
            __page.Response.ContentEncoding = System.Text.Encoding.GetEncoding("UTF-8");
            
            __page.Response.AppendHeader("Content-Disposition", "attachment;filename=\"" + System.Web.HttpUtility.UrlEncode(__strFileName, System.Text.Encoding.UTF8) + ".xls\"");
            //__page.Response.AddHeader("Content-Length", file.Length.ToString());
            __page.Response.Charset = "UTF-8";

            string colHeaders = "", ls_item = "";
            int i = 0;

            //定义表对象与行对像，同时用DataSet对其值进行初始化
            DataTable dt = __dsSource.Tables[0];
            DataRow[] myRow = dt.Select("");
            if (__ef == ExportFormat.ExcelFormat)
            {
                __page.Response.ContentType = "application/ms-excel";//application/vnd.ms-excel
                StringWriter stringWriter = new StringWriter();

                //取得数据表各列标题，各标题之间以\t分割，最后一个列标题后加回车符
                for (i = 0; i < dt.Columns.Count - 1; i++)
                    colHeaders += dt.Columns[i].Caption.ToString() + "\t";
                colHeaders += dt.Columns[i].Caption.ToString() + "\n";
                //向HTTP输出流中写入取得的数据信息
                stringWriter.WriteLine(colHeaders);
                //__page.Response.Write(colHeaders);
                //逐行处理数据  
                foreach (DataRow row in myRow)
                {
                    //在当前行中，逐列获得数据，数据之间以\t分割，结束时加回车符\n
                    for (i = 0; i < dt.Columns.Count - 1; i++)
                        ls_item += row[i].ToString().Replace("\t", "") + "\t";
                    ls_item += row[i].ToString().Replace("\t", "") + "\n";
                    //当前行数据写入HTTP输出流，并且置空ls_item以便下行数据    
                    //__page.Response.Write(ls_item);
                    stringWriter.WriteLine(ls_item);
                    ls_item = "";
                }
                __page.Response.Write(stringWriter.ToString());
            }
            else
            {
                if (__ef == ExportFormat.XMLFormat)
                {
                    //从DataSet中直接导出XML数据并且写到HTTP输出流中
                    __page.Response.Write(__dsSource.GetXml());
                }
            }
            //写缓冲区中的数据到HTTP头文件中
            __page.Response.End();
        }
        catch (Exception e)
        {
            //throw new Exception(e.Message + "-------" + e.Source.ToString());
        }
    }

    /// <summary>
    /// 导出Excel的格式
    /// </summary>
    public enum ExportFormat
    {
        ExcelFormat = 0,            //Excel格式
        XMLFormat = 1                //XML格式
    }
}