Excel[.xls|.xlsx|.csv] 导入 导出

using System.IO;
using System.Data;
using System.Data.OleDb;
using System.Data.Odbc;

 public static DataTable FromExceFile(string pathName)
        {
            DataSet ds = new DataSet();
            try
            {

                FileInfo file = new FileInfo(pathName);
                if (!file.Exists)
                {
                    throw new Exception("Not exist!");
                }
                string ext=file.Extension.ToLower();
                if (ext!=".xls" && ext!="xlsx")
                {
                    throw new Exception("File Extension Must Be:.xls Or .xlsx");
                }

           
                string xlsConn = string.Format(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathName + ""
                    + @";Extended Properties='Excel 8.0;HDR={0};IMEX=1;'", "YES");

                //"HDR=Yes;" 第一行是表头，不是数据
                //"IMEX=1;" 把混合数据当作文本读取
                string xlsxConn= "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + pathName 
                     + ";Extended Properties='Excel 12.0;HDR=Yes;IMEX=1;'";


                OleDbConnection cnn = new OleDbConnection(ext.Equals(".xlsx")?xlsxConn:xlsConn);
                cnn.Open();
                DataTable dttemp = cnn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
                string tableName = dttemp.Rows[0][2].ToString().Trim();

                OleDbCommand com = new OleDbCommand("SELECT * FROM ["+tableName+"]", cnn);
                OleDbDataAdapter objAdapter = new OleDbDataAdapter();
                objAdapter.SelectCommand = com;
                objAdapter.Fill(ds, "TempTable");
                cnn.Close();
                cnn.Dispose();
            }
            catch (OdbcException ex)
            {

            }

            DataTable dt = ds.Tables["TempTable"];
            return dt;
        }

  public static DataTable FromCsvFile(string pathName)
        {
            DataSet ds = new DataSet();
            DataTable dt;
            try
            {

                FileInfo file = new FileInfo(pathName);
                if (!file.Exists)
                {
                    throw new Exception("Not exist!");
                }
                if (file.Extension.ToLower()!=".csv")
                {
                    throw new Exception("File Extension Must Be .csv");
                }
                string csvConn="Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathName 
                      + ";Extended Properties='Text;HDR=YES;'";
                OleDbConnection cnn = new OleDbConnection(csvConn);
                cnn.Open();
                OleDbCommand com = new OleDbCommand("SELECT * FROM ["+file.Name +"]", cnn);
                OleDbDataAdapter da=new OleDbDataAdapter();
                da.SelectCommand = com;
                da.Fill(ds, "TempTable");
                da.Dispose();
                cnn.Close();
                cnn.Dispose();


            }
            catch
            {
                dt=new DataTable();
                return dt;
            }

            dt=ds.Tables["TempTable"];

            return dt;

        }

  public static void ExportExcel()
        {
            List<string[]> exportDataList = new List<string[]>();
            int FieldCount=3;
            string[] titleRow = new string[FieldCount];
            int i=0;
            titleRow[i++]="Name";
            titleRow[i++]="Age";
            titleRow[i++]="Tel";
            exportDataList.Add(titleRow);

            for(int k=0;k<10;k++)
            {
                i=0;
                string[] row = new string[FieldCount];
                row[i++]="Name "+k;
                row[i++]="Age "+k;
                row[i++]="Tel "+k;
                exportDataList.Add(row);
            }
            Export(exportDataList,"export.xls");
        }
        public static void Export(List<string[]> dataList,string fileName)
        {             

            string rowTmp="<td style=\"vnd.ms-excel.numberformat:@\">{0}</td>";
            string html = "";
            html += "<html xmlns:x=\"urn:schemas-microsoft-com:office:excel\">";
            html += "<head>";
            html += "<!--[if gte mso 9]>";
            html += "<xml>";
            html += " <x:ExcelWorkbook>";
            html += " <x:ExcelWorksheets>";
            html += " <x:ExcelWorksheet>";
            html += " <x:Name>Winner</x:Name>";
            html += " <x:WorksheetOptions>";
            html += " <x:Print>";
            html += " <x:ValidPrinterInfo />";
            html += " </x:Print>";
            html += " </x:WorksheetOptions>";
            html += " </x:ExcelWorksheet>";
            html += " </x:ExcelWorksheets>";
            html += "</x:ExcelWorkbook>";
            html += "</xml>";
            html += "<![endif]-->";
            html += "</head>";
            html += "<body>";
            html += "<table>";

            bool IsHeader=true;
            foreach (var row in dataList)
            {
                string r="";
                string rowTemplate=rowTmp;
                if (IsHeader)
                {
                    IsHeader=false;
                    rowTemplate="<td><strong>{0}</strong></td>";
                }                   
                     
                foreach(var fielddata in row)
                {
                    r+=string.Format(rowTemplate, fielddata);
                }                  
             
                html+=(string.Format("<tr>{0}</tr>", r));
            }
                  
         
            html += "</table>";
            html += "</body>";
            html += "</html>";


            HttpResponse resp=Page.Response;
            resp.ContentEncoding = System.Text.Encoding.Default;
            resp.AppendHeader("Content-Disposition", "attachment;filename="+fileName);
            resp.ContentType = "application/ms-excel";
            resp.Clear();
            resp.Write(html);
            resp.Flush();
            resp.End();
        }

 Excel单元格的格式：

 使用<td style="vnd.ms-excel.numberformat:@"></td> 进行设置

    //1） 文本：vnd.ms-excel.numberformat:@
    //2） 日期：vnd.ms-excel.numberformat:yyyy/mm/dd
    //3） 数字：vnd.ms-excel.numberformat:#,##0.00
    //4） 货币：vnd.ms-excel.numberformat:￥#,##0.00
    //5） 百分比：vnd.ms-excel.numberformat: #0.00%

<Workbook xmlns="urn:schemas-microsoft-com:office:spreadsheet"
   xmlns:x="urn:schemas-microsoft-com:office:excel"
   xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet"
   xmlns:html="http://www.w3.org/TR/REC-html40">

<x:ExcelWorkbook>
    <WindowHeight>1000</WindowHeight>
    <WindowWidth>1000</WindowWidth>     
</x:ExcelWorkbook>

<ss:Styles>
    <ss:Style ss:ID="Default" ss:Name="Normal">
        <Font x:Family="Swiss" ss:Size="10" ss:Bold="0"/>
        <ss:Alignment ss:Vertical="Bottom"/>
    </ss:Style>
    <ss:Style ss:ID="s22">
        <Font x:Family="Swiss" ss:Size="12" ss:Bold="1"/>
        <ss:NumberFormat ss:Format="0.00;[Red]0.00"/>
    </ss:Style>
</ss:Styles>
 

<Worksheet ss:Name="Sheet one">  
      
    <ss:Table>
        <ss:Row>
            <ss:Cell>
                <ss:Data ss:Type="String">Total</ss:Data>
            </ss:Cell>
            <ss:Cell ss:StyleID="s22">
                <ss:Data ss:Type="Number">-45</ss:Data>
            </ss:Cell>
            <ss:Cell ss:StyleID="s22">
                <ss:Data ss:Type="Number">-99.3</ss:Data>
            </ss:Cell>

           <ss:Cell ss:Index="8" ss:Formula="=AVERAGE(RC[-6]:RC[-5])"></ss:Cell>
           </ss:Row>

           <ss:Row>
            <ss:Cell ss:MergeAcross="1" ss:MergeDown="1">
            <ss:Data ss:Type="String">Monday tip</ss:Data>
            <ss:Comment ss:Author="Author" ss:ShowAlways="1">
                 <ss:Data><html:B><html:Font html:Face="Tahoma" html:Size="8" html:Color="000000">Author:</html:Font></html:B>
                                  <html:Font html:Face="Tahoma" html:Size="8" html:Color="000000">&10;The </html:Font>
                          <html:B><html:Font html:Face="Tahoma" x:Family="Swiss" html:Size="8" html:Color="000000">first</html:Font></html:B>
                                  <html:Font html:Face="Tahoma" x:Family="Swiss" html:Size="8" html:Color="000000"> day of the week.</html:Font>
                  </ss:Data>
              </ss:Comment>
            </ss:Cell>
           <ss:Cell ss:Index="7" ss:HRef="http://www.microsoft.com">
                      <ss:Data ss:Type="String">Linked Cell</ss:Data>
           </ss:Cell>

        </ss:Row>
    </ss:Table> 
</Worksheet>



</Workbook>

 该实例使用的命名空间：

   xmlns="urn:schemas-microsoft-com:office:spreadsheet"
   xmlns:x="urn:schemas-microsoft-com:office:excel"
   xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet"
   xmlns:html="http://www.w3.org/TR/REC-html40"