public DataSet ExcelToDS(string Path)   {    　　string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" +"Data Source="+ Path +";"+"Extended Properties=Excel 8.0;";    OleDbConnection conn = new OleDbConnection(strConn);    　　conn.Open();    string strExcel = "";    OleDbDataAdapter myCommand = null;    DataSet ds = null;    strExcel="select * from [sheet1$]";    myCommand = new OleDbDataAdapter(strExcel, strConn);    ds = new DataSet();    myCommand.Fill(ds,"table1");    return ds; }

string strConn = "Provider=Microsoft.Jet.OLEDB.4.0;" +"Data Source="+ Path +";"+"Extended Properties=Excel 8.0;"; OleDbConnection conn = new OleDbConnection(strConn); DataTable schemaTable = objConn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables,null); string tableName=schemaTable.Rows[0][2].ToString().Trim();  

public void DSToExcel(string Path,DataSet oldds)   {    //先得到汇总Excel的DataSet 主要目的是获得Excel在DataSet中的结构    string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source ="+path1+";Extended Properties=Excel 8.0" ; OleDbConnection myConn = new OleDbConnection(strCon) ; string strCom="select * from [Sheet1$]"; myConn.Open ( ) ; OleDbDataAdapter myCommand = new OleDbDataAdapter ( strCom, myConn ) ; ystem.Data.OleDb.OleDbCommandBuilder builder=new OleDbCommandBuilder(myCommand);    //QuotePrefix和QuoteSuffix主要是对builder生成InsertComment命令时使用。    builder.QuotePrefix="[";     //获取insert语句中保留字符（起始位置） builder.QuoteSuffix="]"; //获取insert语句中保留字符（结束位置）  DataSet newds=new DataSet(); myCommand.Fill(newds ,"Table1") ; for(int i=0;i<oldds.Tables[0].Rows.Count;i++)    {     　　//在这里不能使用ImportRow方法将一行导入到news中， 　　//因为ImportRow将保留原来DataRow的所有设置(DataRowState状态不变)。 　　//在使用ImportRow后newds内有值，但不能更新到Excel中因为所有导入行的DataRowState!=Added 　　DataRow nrow=aDataSet.Tables["Table1"].NewRow();    for(int j=0;j<newds.Tables[0].Columns.Count;j++)    {      　　　　nrow[j]=oldds.Tables[0].Rows[i][j];    }     　　　　newds.Tables["Table1"].Rows.Add(nrow);   }    myCommand.Update(newds,"Table1"); myConn.Close(); }

//读取EXCEL的方法   (用范围区域读取数据) private void OpenExcel(string strFileName)  {      object missing = System.Reflection.Missing.Value;      Application excel = new Application();//lauch excel application if (excel == null)     {          Response.Write("<script>alert('Can't access excel')</script>");      }     else     {          　　excel.Visible = false; 　　excel.UserControl = true;          // 以只读的形式打开EXCEL文件     Workbook wb = excel.Application.Workbooks.Open(strFileName, missing, true, missing, missing, missing,missing, missing, missing, true, missing, missing, missing, missing, missing);          //取得第一个工作薄      Worksheet ws = (Worksheet)wb.Worksheets.get_Item(1);           //取得总记录行数   (包括标题列)       int rowsint = ws.UsedRange.Cells.Rows.Count; //得到行数          　　//int columnsint = mySheet.UsedRange.Cells.Columns.Count;//得到列数           　　//取得数据范围区域  (不包括标题列)    Range rng1 = ws.Cells.get_Range("B2", "B" + rowsint);   //item             Range rng2 = ws.Cells.get_Range("K2", "K" + rowsint);  //Customer          　 object[,] arryItem= (object[,])rng1.Value2;   //get range's value            object[,] arryCus = (object[,])rng2.Value2;             //将新值赋给一个数组            string[,] arry = new string[rowsint-1, 2];            for (int i = 1; i <= rowsint-1; i++)           {              　　  //Item_Code列              　　 arry[i - 1, 0] =arryItem[i, 1].ToString();              //Customer_Name列              　　arry[i - 1, 1] = arryCus[i, 1].ToString();          }         Response.Write(arry[0, 0] + "  /  " + arry[0, 1] + "#" + arry[rowsint - 2, 0] + "  /  " + arry[rowsint - 2, 1]);      }         excel.Quit();  　excel = null;     Process[] procs = Process.GetProcessesByName("excel");  foreach (Process pro in procs)      {          　　pro.Kill();//没有更好的方法,只有杀掉进程     }      GC.Collect();  }

using System.Text;和using System.IO;            FileStream fs = new FileStream("d:\\Customer.csv", FileMode.Open, FileAccess.Read, FileShare.None); StreamReader sr = new StreamReader(fs, System.Text.Encoding.GetEncoding(936)); string str = "";            string s = Console.ReadLine();            while (str != null)            {    　　str = sr.ReadLine(); 　　string[] xu = new String[2]; 　　xu = str.Split(','); 　　string ser = xu[0]; 　　string dse = xu[1]; 　　if (ser == s) 　　{  　　　　Console.WriteLine(dse);break; 　　}           }   sr.Close();

//txt文件名  string fn = DateTime.Now.ToString("yyyyMMddHHmmss") + "-" + "PO014" + ".txt";   OleDbConnection con = new OleDbConnection(conStr);   con.Open();  string sql = "select  ITEM,REQD_DATE,QTY,PUR_FLG,PO_NUM from TSD_PO014";          OleDbCommand mycom = new OleDbCommand("select * from TSD_PO014", mycon);  //OleDbDataReader myreader = mycom.ExecuteReader();  //也可以用Reader读取数据 DataSet ds = new DataSet();  OleDbDataAdapter oda = new OleDbDataAdapter(sql, con); oda.Fill(ds, "PO014");  DataTable dt = ds.Tables[0];  FileStream fs = new FileStream(Server.MapPath("download/" + fn), FileMode.Create, FileAccess.ReadWrite);  StreamWriter strmWriter = new StreamWriter(fs);    //存入到文本文件中    //把标题写入.txt文件中  //for (int i = 0; i <dt.Columns.Count;i++)  //{  //    strmWriter.Write(dt.Columns[i].ColumnName + "  "); //}  foreach (DataRow dr in dt.Rows)  {     　　string str0, str1, str2, str3;      　　string str = "|";  //数据用"|"分隔开    　　str0 = dr[0].ToString();      　　str1 = dr[1].ToString();    　　str2 = dr[2].ToString();  　　str3 = dr[3].ToString();      str4 = dr[4].ToString().Trim();      strmWriter.Write(str0);      strmWriter.Write(str);     strmWriter.Write(str1);      strmWriter.Write(str);     strmWriter.Write(str2);      strmWriter.Write(str);      strmWriter.Write(str3);     strmWriter.WriteLine();  //换行  }  strmWriter.Flush(); strmWriter.Close(); if (con.State == ConnectionState.Open)  {     　　con.Close(); }