C# 讀取EXCEL檔案的三種經典方法

1.方法一：採用OleDB讀取EXCEL檔案： 
把EXCEL檔案當做一個資料來源來進行資料的讀取操作，執行個體如下： 

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; } 

對於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 = "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();   

另外：也可進行寫入EXCEL檔案，執行個體如下： 

public void DSToExcel(string Path,DataSet oldds) { //先得到匯總EXCEL的DataSet 主要目的是獲得EXCEL在DataSet中的結構 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主要是對builder產生InsertComment命令時使用。 builder.QuotePrefix="[";     //擷取insert語句中保留字元（起始位置） builder.QuoteSuffix="]"; //擷取insert語句中保留字元（結束位置） DataSet newds=new DataSet(); myCommand.Fill(newds ,"Table1") ; for(int i=0;i<oldds.Tables[0].Rows.Count;i++) { //在這裡不能使用ImportRow方法將一行匯入到news中，因為ImportRow將保留原來DataRow的所有設定(DataRowState狀態不變)。   在使用ImportRow後newds內有值，但不能更新到Excel中因為所有匯入行的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(); } 

2.方法二：引用的com組件：Microsoft.Office.Interop.Excel.dll   讀取EXCEL檔案 
首先是Excel.dll的擷取,將Office安裝目錄下的Excel.exe檔案Copy到DotNet的bin目錄下,cmd到該目錄下,運行 TlbImp EXCEL.EXE Excel.dll 得到Dll檔案。 再在項目中添加引用該dll檔案. 

    //讀取EXCEL的方法   (用範圍地區讀取資料)    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;            // 以唯讀形式開啟EXCEL檔案            Workbook wb = excel.Application.Workbooks.Open(strFileName, missing, true, missing, missing, missing,             missing, missing, missing, true, missing, missing, missing, missing, missing);            //取得第一個工作薄            Worksheet ws = (Worksheet)wb.Worksheets.get_Item(1);            //取得總記錄行數   (包括標題列)            int rowsint = ws.UsedRange.Cells.Rows.Count; //得到行數            //int columnsint = mySheet.UsedRange.Cells.Columns.Count;//得到列數            //取得資料範圍地區 (不包括標題列)             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;               //將新值賦給一個數組            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();//沒有更好的方法,只有殺掉進程        }        GC.Collect();    }

3.方法三：將EXCEL檔案轉化成CSV（逗號分隔）的檔案，用檔案流讀取(等價就是讀取一個txt文字檔)。 

           先引用命名空間: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();

另外也可以將資料庫資料匯入到一個txt檔案，執行個體如下： 
 

           //txt檔案名稱        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讀取資料        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);    //存入到文字檔中         //把標題寫入.txt檔案中         //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 = "|"; //資料用"|"分隔開            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(); //換行        }        strmWriter.Flush();        strmWriter.Close();        if (con.State == ConnectionState.Open)        {            con.Close();

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