.net读取Excel文件的三种经典方法

1.方法一&＃xff1a;采用OleDB读取EXCEL文件&＃xff1a;
  把EXCEL文件当做一个数据源来进行数据的读取操作&＃xff0c;实例如下&＃xff1a;
public DataSet ExcelToDS(string Path)
{
 string strConn &＃61; "Provider&＃61;Microsoft.Jet.OLEDB.4.0;" &＃43;"Data Source&＃61;"&＃43; Path &＃43;";"&＃43;"Extended Properties&＃61;Excel 8.0;";
 OleDbConnection conn &＃61; new OleDbConnection(strConn);
 conn.Open();  
 string strExcel &＃61; "";   
 OleDbDataAdapter myCommand &＃61; null;
 DataSet ds &＃61; null;
 strExcel&＃61;"select * from [sheet1$]";
 myCommand &＃61; new OleDbDataAdapter(strExcel, strConn);
 ds &＃61; new DataSet();
 myCommand.Fill(ds,"table1");   
 return ds;
}
对于EXCEL中的表即sheet([sheet1$])如果不是固定的可以使用下面的方法得到
 string strConn &＃61; "Provider&＃61;Microsoft.Jet.OLEDB.4.0;" &＃43;"Data Source&＃61;"&＃43; Path &＃43;";"&＃43;"Extended Properties&＃61;Excel 8.0;";
 OleDbConnection conn &＃61; new OleDbConnection(strConn);
 DataTable schemaTable &＃61; objConn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables,null);
 string tableName&＃61;schemaTable.Rows[0][2].ToString().Trim();  

另外&＃xff1a;也可进行写入EXCEL文件&＃xff0c;实例如下&＃xff1a;
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 &＃61; " Provider &＃61; Microsoft.Jet.OLEDB.4.0 ; Data Source &＃61;"&＃43;path1&＃43;";Extended Properties&＃61;Excel 8.0" ;
 OleDbConnection myConn &＃61; new OleDbConnection(strCon) ;
 string strCom&＃61;"select * from [Sheet1$]";
 myConn.Open ( ) ;
 OleDbDataAdapter myCommand &＃61; new OleDbDataAdapter ( strCom, myConn ) ;
 ystem.Data.OleDb.OleDbCommandBuilder builder&＃61;new OleDbCommandBuilder(myCommand);
 //QuotePrefix和QuoteSuffix主要是对builder生成InsertComment命令时使用。
 builder.QuotePrefix&＃61;"[";     //获取insert语句中保留字符&＃xff08;起始位置&＃xff09;
 builder.QuoteSuffix&＃61;"]"; //获取insert语句中保留字符&＃xff08;结束位置&＃xff09;
 DataSet newds&＃61;new DataSet();
 myCommand.Fill(newds ,"Table1") ;
 for(int i&＃61;0;i  {
  //在这里不能使用ImportRow方法将一行导入到news中&＃xff0c;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&＃xff0c;但不能更新到Excel中因为所有导入行的DataRowState!&＃61;Added
  DataRow nrow&＃61;aDataSet.Tables["Table1"].NewRow();
  for(int j&＃61;0;j   {
   nrow[j]&＃61;oldds.Tables[0].Rows[i][j];
  }
  newds.Tables["Table1"].Rows.Add(nrow);
 }
 myCommand.Update(newds,"Table1");
 myConn.Close();
}

2.方法二&＃xff1a;引用的com组件&＃xff1a;Microsoft.Office.Interop.Excel.dll   读取EXCEL文件
  首先是Excel.dll的获取,将Office安装目录下的Excel.exe文件Copy到DotNet的bin目录下,cmd到该目录下,运行 TlbImp EXCEL.EXE Excel.dll 得到Dll文件。 点击此处下载此文件&＃xff1a;/Files/songliang/DLL文件.rar
   再在项目中添加引用该dll文件.

    //读取EXCEL的方法   (用范围区域读取数据)
    private void OpenExcel(string strFileName)
    {
        object missing &＃61; System.Reflection.Missing.Value;
        Application excel &＃61; new Application();//lauch excel application
        if (excel &＃61;&＃61; null)
        {
            Response.Write("");
        }
        else
        {
            excel.Visible &＃61; false;  excel.UserControl &＃61; true;
            // 以只读的形式打开EXCEL文件
            Workbook wb &＃61; 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 &＃61; (Worksheet)wb.Worksheets.get_Item(1);

            //取得总记录行数   (包括标题列)
            int rowsint &＃61; ws.UsedRange.Cells.Rows.Count; //得到行数
            //int columnsint &＃61; 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 &＃61; ws.Cells.get_Range("B2", "B" &＃43; rowsint);   //item

            Range rng2 &＃61; ws.Cells.get_Range("K2", "K" &＃43; rowsint);  //Customer
            object[,] arryItem&＃61; (object[,])rng1.Value2;   //get range&＃39;s value
            object[,] arryCus &＃61; (object[,])rng2.Value2;  
            //将新值赋给一个数组
            string[,] arry &＃61; new string[rowsint-1, 2];
            for (int i &＃61; 1; i <&＃61; rowsint-1; i&＃43;&＃43;)
            {
                //Item_Code列
                arry[i - 1, 0] &＃61;arryItem[i, 1].ToString();
                //Customer_Name列
                arry[i - 1, 1] &＃61; arryCus[i, 1].ToString();
            }
            Response.Write(arry[0, 0] &＃43; "  /  " &＃43; arry[0, 1] &＃43; "#" &＃43; arry[rowsint - 2, 0] &＃43; "  /  " &＃43; arry[rowsint - 2, 1]);
        }
         excel.Quit();  excel &＃61; null;
        Process[] procs &＃61; 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();
    }

3.方法三&＃xff1a;将EXCEL文件转化成CSV&＃xff08;逗号分隔&＃xff09;的文件&＃xff0c;用文件流读取(等价就是读取一个txt文本文件)。
           先引用命名空间:using System.Text;和using System.IO;
           FileStream fs &＃61; new FileStream("d:\\Customer.csv", FileMode.Open, FileAccess.Read, FileShare.None);
           StreamReader sr &＃61; new StreamReader(fs, System.Text.Encoding.GetEncoding(936));

           string str &＃61; "";
           string s &＃61; Console.ReadLine();
           while (str !&＃61; null)
           {    str &＃61; sr.ReadLine();
                string[] xu &＃61; new String[2];
                xu &＃61; str.Split(&＃39;,&＃39;);
                string ser &＃61; xu[0];
                string dse &＃61; xu[1];                if (ser &＃61;&＃61; s)
                {  Console.WriteLine(dse);break;
                }
           }   sr.Close();
 
另外也可以将数据库数据导入到一个txt文件&＃xff0c;实例如下&＃xff1a;
   
        //txt文件名
        string fn &＃61; DateTime.Now.ToString("yyyyMMddHHmmss") &＃43; "-" &＃43; "PO014" &＃43; ".txt";

        OleDbConnection con &＃61; new OleDbConnection(conStr);
        con.Open();
        string sql &＃61; "select  ITEM,REQD_DATE,QTY,PUR_FLG,PO_NUM from TSD_PO014";       
       //OleDbCommand mycom &＃61; new OleDbCommand("select * from TSD_PO014", mycon);
        //OleDbDataReader myreader &＃61; mycom.ExecuteReader();  //也可以用Reader读取数据
        DataSet ds &＃61; new DataSet();
        OleDbDataAdapter oda &＃61; new OleDbDataAdapter(sql, con);
        oda.Fill(ds, "PO014");
        DataTable dt &＃61; ds.Tables[0];

        FileStream fs &＃61; new FileStream(Server.MapPath("download/" &＃43; fn), FileMode.Create, FileAccess.ReadWrite);
        StreamWriter strmWriter &＃61; new StreamWriter(fs);    //存入到文本文件中
 
        //把标题写入.txt文件中
        //for (int i &＃61; 0; i         //{
        //    strmWriter.Write(dt.Columns[i].ColumnName &＃43; "  ");
        //}
       
        foreach (DataRow dr in dt.Rows)
        {
            string str0, str1, str2, str3;
            string str &＃61; "|";  //数据用"|"分隔开
            str0 &＃61; dr[0].ToString();
            str1 &＃61; dr[1].ToString();
            str2 &＃61; dr[2].ToString();
            str3 &＃61; dr[3].ToString();
            str4 &＃61; 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 &＃61;&＃61; ConnectionState.Open)
        {
            con.Close();
        }