用c讀取excel的三種方法

1、C#讀取Excel的三種方法及比較（1）OleDB方式優(yōu)點：將Excel直接當(dāng)做數(shù)據(jù)源處理，通過SQL直接讀取內(nèi)容，讀取速度較快。缺點：讀取數(shù)據(jù)方式不夠靈活，無法直接讀取某一個單元格，只有將整個Sheet頁讀取出來后（結(jié)果為Datatable）再在Datatable中根據(jù)行列數(shù)來獲取指定的值。           當(dāng)Excel數(shù)據(jù)量很大時。會非常占用內(nèi)存，當(dāng)內(nèi)存不夠時會拋出內(nèi)存溢出的異常。讀取代碼如下： 1: public DataTable GetExcelTableByOleDB(strin

2、g strExcelPath, string tableName) 2: 3: try 4: 5: DataTable dtExcel = new DataTable(); 6: /數(shù)據(jù)表 7: DataSet ds = new DataSet(); 8: /獲取文件擴展名 9: string strExtension = System.IO.Path.GetExtension(strExcelPath); 10: string strFileName = System.IO.Path.GetFileName(strExcelPath); 11: /Excel的連接 12: OleDbConn

3、ection objConn = null; 13: switch (strExtension) 14: 15: case ".xls": 16: objConn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + strExcelPath + "" + "Extended Properties="Excel 8.0;HDR=NO;IMEX=1;""); 17: break; 18: case "

4、;.xlsx": 19: objConn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + strExcelPath + "" + "Extended Properties="Excel 12.0;HDR=NO;IMEX=1;""); 20: break; 21: default: 22: objConn = null; 23: break; 24: 25: if (objConn = null) 26: 27

5、: return null; 28: 29: objConn.Open(); 30: /獲取Excel中所有Sheet表的信息 31: /System.Data.DataTable schemaTable = objConn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables, null); 32: /獲取Excel的第一個Sheet表名 33: /string tableName = schemaTable.Rows02.ToString().Trim(); 34: string strSql = "select

6、 * from " + tableName + "" 35: /獲取Excel指定Sheet表中的信息 36: OleDbCommand objCmd = new OleDbCommand(strSql, objConn); 37: OleDbDataAdapter myData = new OleDbDataAdapter(strSql, objConn); 38: myData.Fill(ds, tableName);/填充數(shù)據(jù) 39: objConn.Close(); 40: /dtExcel即為excel文件中指定表中存儲的信息 41: dtExcel =

7、 ds.TablestableName; 42: return dtExcel; 43: 44: catch 45: 46: return null; 47: 48: 下面說明一下連接字符串        HDR=Yes，這代表第一行是標(biāo)題，不做為數(shù)據(jù)使用（但是我在實際使用中，如果第一行存在復(fù)雜數(shù)值，那么讀取得到的Datatable列標(biāo)題會自動設(shè)置為F1、F2等方式命名，與實際應(yīng)用不符，所以當(dāng)時是通過HDR=No方式將所有內(nèi)容讀取到Datatable中，然后手動將第一行設(shè)置成標(biāo)題的）；IMEX ( IMport EXport

8、 mode )設(shè)置 IMEX 有三種模式： 0 is Export mode 1 is Import mode 2 is Linked mode (full update capabilities) 我這里特別要說明的就是 IMEX 參數(shù)了，因為不同的模式代表著不同的讀寫行為： 當(dāng) IMEX=0 時為“匯出模式”，這個模式開啟的 Excel 檔案只能用來做“寫入”用途。 當(dāng) IMEX=1 時為“匯入模式”，這個模式開啟的 Excel 檔案只能用來做“讀取”用途。 當(dāng) IMEX=2 時為“鏈接模式”，這個模式開啟的

9、Excel 檔案可同時支援“讀取”與“寫入”用途。-另外，讀取Excel2007版本的文件時，版本應(yīng)該從8.0改為12.0，同時驅(qū)動不能再用Jet，而應(yīng)該用ACE。負責(zé)會造成“找不到可安裝的 ISAM”的錯誤。-在網(wǎng)上還發(fā)現(xiàn)采用這種方式存在取出的Sheet表的個數(shù)多于實際Excel表中的Sheet表個數(shù)的情況，其原因有二：1. 取出的名稱中，包括了XL命名管理器中的名稱（參見XL2007的公式-命名管理器， 快捷鍵Crtl+F3）；2. 取出的名稱中，包括了FilterDatabase后綴的， 這是XL用來記錄Filter范圍的。對于第一點比較簡單， 刪除已有命名管理器中的內(nèi)容即可；第二點處理

10、起來比較麻煩， Filter刪除后這些名稱依然保留著，簡單的做法是新增Sheet然后將原Sheet Copy進去。但實際情況并不能為每個Excel做以上檢查。下面給出了過濾的方案。（此問題我們有驗證過，大家自己驗證一下吧） 1: /objConn為讀取Excel的鏈接，下面通過過濾來獲取有效的Sheet頁名稱集合 2: System.Data.DataTable schemaTable = objConn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables, null); 3: List<string> lstS

11、heetNames = new List<string>(); 4: for (int i = 0; i < schemaTable.Rows.Count; i+) 5: 6: string strSheetName = (string)dtSheetName.Rowsi"TABLE_NAME" 7: if (strSheetName.Contains("$") && !strSheetName.Replace("'", "").EndsWith("$"

12、) 8: 9: /過濾無效SheetName完畢. 10: continue; 11: 12: if (lstSheetNames != null && !lstSheetNames.Contains(strSheetName) 13: lstSheetNames.Add(strSheetName); 14: 因為讀取出來無效SheetName一般情況最后一個字符都不會是$。如果SheetName有一些特殊符號，讀取出來的SheetName會自動加上單引號。比如在Excel中將SheetName編輯成MySheet(1)，此時讀取出來的SheetName就為：'MySh

13、eet(1)$'，所以判斷最后一個字符是不是$之前最好過濾一下單引號。-（2）Com組件的方式（通過添加 Microsoft.Office.Interop.Excel引用實現(xiàn)）優(yōu)點：能夠非常靈活的讀取Excel中的數(shù)據(jù)，用戶可以靈活的調(diào)用各種函數(shù)進行處理。缺點：基于單元格的處理，讀取速度較慢，對于數(shù)據(jù)量較大的文件最好不要使用此種方式讀取。           需要添加相應(yīng)的DLL引用，必須存在此引用才可使用，如果是Web站點部署在IIS上時，還需要服務(wù)器機子已安裝了Excel，有時候還需

14、要為配置IIS權(quán)限。讀取代碼如下： 1: private Stopwatch wath = new Stopwatch(); 2: / <summary> 3: / 使用COM讀取Excel 4: / </summary> 5: / <param name="excelFilePath">路徑</param> 6: / <returns>DataTabel</returns> 7: public System.Data.DataTable GetExcelData(string excelFilePat

15、h) 8: 9: Excel.Application app = new Excel.Application(); 10: Excel.Sheets sheets; 11: Excel.Workbook workbook = null; 12: object oMissiong = System.Reflection.Missing.Value; 13: System.Data.DataTable dt = new System.Data.DataTable(); 14: wath.Start(); 15: try 16: 17: if (app = null) 18: 19: return

16、null; 20: 21: workbook = app.Workbooks.Open(excelFilePath, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, 22: oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong); 23: /將數(shù)據(jù)讀入到DataTable中Start 24: sheets = workbook.Worksheets; 25: Excel.Worksheet w

17、orksheet = (Excel.Worksheet)sheets.get_Item(1);/讀取第一張表 26: if (worksheet = null) 27: return null; 28: string cellContent; 29: int iRowCount = worksheet.UsedRange.Rows.Count; 30: int iColCount = worksheet.UsedRange.Columns.Count; 31: Excel.Range range; 32: /負責(zé)列頭Start 33: DataColumn dc; 34: int Column

18、ID = 1; 35: range = (Excel.Range)worksheet.Cells1, 1; 36: while (range.Text.ToString().Trim() != "") 37: 38: dc = new DataColumn(); 39: dc.DataType = System.Type.GetType("System.String"); 40: dc.ColumnName = range.Text.ToString().Trim(); 41: dt.Columns.Add(dc); 42: 43: range = (E

19、xcel.Range)worksheet.Cells1, +ColumnID; 44: 45: /End 46: for (int iRow = 2; iRow <= iRowCount; iRow+) 47: 48: DataRow dr = dt.NewRow(); 49: for (int iCol = 1; iCol <= iColCount; iCol+) 50: 51: range = (Excel.Range)worksheet.CellsiRow, iCol; 52: cellContent = (range.Value2 = null) ? ""

20、; : range.Text.ToString(); 53: driCol - 1 = cellContent; 54: 55: dt.Rows.Add(dr); 56: 57: wath.Stop(); 58: TimeSpan ts = wath.Elapsed; 59: /將數(shù)據(jù)讀入到DataTable中End 60: return dt; 61: 62: catch 63: 64: return null; 65: 66: finally 67: 68: workbook.Close(false, oMissiong, oMissiong); 69: System.Runtime.In

21、teropServices.Marshal.ReleaseComObject(workbook); 70: workbook = null; 71: app.Workbooks.Close(); 72: app.Quit(); 73: System.Runtime.InteropServices.Marshal.ReleaseComObject(app); 74: app = null; 75: GC.Collect(); 76: GC.WaitForPendingFinalizers(); 77: 78: 79: / <summary> 80: / 使用COM，多線程讀取Exce

22、l（1 主線程、4 副線程） 81: / </summary> 82: / <param name="excelFilePath">路徑</param> 83: / <returns>DataTabel</returns> 84: public System.Data.DataTable ThreadReadExcel(string excelFilePath) 85: 86: Excel.Application app = new Excel.Application(); 87: Excel.Sheets she

23、ets = null; 88: Excel.Workbook workbook = null; 89: object oMissiong = System.Reflection.Missing.Value; 90: System.Data.DataTable dt = new System.Data.DataTable(); 91: wath.Start(); 92: try 93: 94: if (app = null) 95: 96: return null; 97: 98: workbook = app.Workbooks.Open(excelFilePath, oMissiong, o

24、Missiong, oMissiong, oMissiong, oMissiong, oMissiong, 99: oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong); 100: /將數(shù)據(jù)讀入到DataTable中Start 101: sheets = workbook.Worksheets; 102: Excel.Worksheet worksheet = (Excel.Worksheet)sheets.get_Item(1);/讀取第一張表 103: if (work

25、sheet = null) 104: return null; 105: string cellContent; 106: int iRowCount = worksheet.UsedRange.Rows.Count; 107: int iColCount = worksheet.UsedRange.Columns.Count; 108: Excel.Range range; 109: /負責(zé)列頭Start 110: DataColumn dc; 111: int ColumnID = 1; 112: range = (Excel.Range)worksheet.Cells1, 1; 113:

26、 while (iColCount >= ColumnID) 114: 115: dc = new DataColumn(); 116: dc.DataType = System.Type.GetType("System.String"); 117: string strNewColumnName = range.Text.ToString().Trim(); 118: if (strNewColumnName.Length = 0) strNewColumnName = "_1" 119: /判斷列名是否重復(fù) 120: for (int i =

27、1; i < ColumnID; i+) 121: 122: if (dt.Columnsi - 1.ColumnName = strNewColumnName) 123: strNewColumnName = strNewColumnName + "_1" 124: 125: dc.ColumnName = strNewColumnName; 126: dt.Columns.Add(dc); 127: range = (Excel.Range)worksheet.Cells1, +ColumnID; 128: 129: /End 130: /數(shù)據(jù)大于500條，使用多

28、進程進行讀取數(shù)據(jù) 131: if (iRowCount - 1 > 500) 132: 133: /開始多線程讀取數(shù)據(jù) 134: /新建線程 135: int b2 = (iRowCount - 1) / 10; 136: DataTable dt1 = new DataTable("dt1"); 137: dt1 = dt.Clone(); 138: SheetOptions sheet1thread = new SheetOptions(worksheet, iColCount, 2, b2 + 1, dt1); 139: Thread othread1 = ne

29、w Thread(new ThreadStart(sheet1thread.SheetToDataTable); 140: othread1.Start(); 141: /阻塞 1 毫秒，保證第一個讀取 dt1 142: Thread.Sleep(1); 143: DataTable dt2 = new DataTable("dt2"); 144: dt2 = dt.Clone(); 145: SheetOptions sheet2thread = new SheetOptions(worksheet, iColCount, b2 + 2, b2 * 2 + 1, dt2)

30、; 146: Thread othread2 = new Thread(new ThreadStart(sheet2thread.SheetToDataTable); 147: othread2.Start(); 148: DataTable dt3 = new DataTable("dt3"); 149: dt3 = dt.Clone(); 150: SheetOptions sheet3thread = new SheetOptions(worksheet, iColCount, b2 * 2 + 2, b2 * 3 + 1, dt3); 151: Thread oth

31、read3 = new Thread(new ThreadStart(sheet3thread.SheetToDataTable); 152: othread3.Start(); 153: DataTable dt4 = new DataTable("dt4"); 154: dt4 = dt.Clone(); 155: SheetOptions sheet4thread = new SheetOptions(worksheet, iColCount, b2 * 3 + 2, b2 * 4 + 1, dt4); 156: Thread othread4 = new Threa

32、d(new ThreadStart(sheet4thread.SheetToDataTable); 157: othread4.Start(); 158: /主線程讀取剩余數(shù)據(jù) 159: for (int iRow = b2 * 4 + 2; iRow <= iRowCount; iRow+) 160: 161: DataRow dr = dt.NewRow(); 162: for (int iCol = 1; iCol <= iColCount; iCol+) 163: 164: range = (Excel.Range)worksheet.CellsiRow, iCol; 16

33、5: cellContent = (range.Value2 = null) ? "" : range.Text.ToString(); 166: driCol - 1 = cellContent; 167: 168: dt.Rows.Add(dr); 169: 170: othread1.Join(); 171: othread2.Join(); 172: othread3.Join(); 173: othread4.Join(); 174: /將多個線程讀取出來的數(shù)據(jù)追加至 dt1 后面 175: foreach (DataRow dr in dt.Rows) 176:

34、 dt1.Rows.Add(dr.ItemArray); 177: dt.Clear(); 178: dt.Dispose(); 179: foreach (DataRow dr in dt2.Rows) 180: dt1.Rows.Add(dr.ItemArray); 181: dt2.Clear(); 182: dt2.Dispose(); 183: foreach (DataRow dr in dt3.Rows) 184: dt1.Rows.Add(dr.ItemArray); 185: dt3.Clear(); 186: dt3.Dispose(); 187: foreach (Dat

35、aRow dr in dt4.Rows) 188: dt1.Rows.Add(dr.ItemArray); 189: dt4.Clear(); 190: dt4.Dispose(); 191: return dt1; 192: 193: else 194: 195: for (int iRow = 2; iRow <= iRowCount; iRow+) 196: 197: DataRow dr = dt.NewRow(); 198: for (int iCol = 1; iCol <= iColCount; iCol+) 199: 200: range = (Excel.Rang

36、e)worksheet.CellsiRow, iCol; 201: cellContent = (range.Value2 = null) ? "" : range.Text.ToString(); 202: driCol - 1 = cellContent; 203: 204: dt.Rows.Add(dr); 205: 206: 207: wath.Stop(); 208: TimeSpan ts = wath.Elapsed; 209: /將數(shù)據(jù)讀入到DataTable中End 210: return dt; 211: 212: catch 213: 214: ret

37、urn null; 215: 216: finally 217: 218: workbook.Close(false, oMissiong, oMissiong); 219: System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook); 220: System.Runtime.InteropServices.Marshal.ReleaseComObject(sheets); 221: workbook = null; 222: app.Workbooks.Close(); 223: app.Quit(); 224: Sys

38、tem.Runtime.InteropServices.Marshal.ReleaseComObject(app); 225: app = null; 226: GC.Collect(); 227: GC.WaitForPendingFinalizers(); 228: 229: -（3）NPOI方式讀取Excel（此方法未經(jīng)過測試）NPOI 是 POI 項目的 .NET 版本。POI是一個開源的Java讀寫Excel、WORD等微軟OLE2組件文檔的項目。使用 NPOI 你就可以在沒有安裝 Office 或者相應(yīng)環(huán)境的機器上對 WORD/EXCEL 文檔進行讀寫。優(yōu)點：讀

39、取Excel速度較快，讀取方式操作靈活性缺點：需要下載相應(yīng)的插件并添加到系統(tǒng)引用當(dāng)中。 1: / <summary> 2: / 將excel中的數(shù)據(jù)導(dǎo)入到DataTable中 3: / </summary> 4: / <param name="sheetName">excel工作薄sheet的名稱</param> 5: / <param name="isFirstRowColumn">第一行是否是DataTable的列名</param> 6: / <returns>返回的DataTable</returns> 7: public DataTable ExcelToDataTable(string sheetName, bool isFirstRowColumn) 8: 9: ISheet sheet = null; 10: DataTable data = new DataTable(); 11: int startRow = 0; 12: try 13: 14: fs = new FileStream(fileName, FileMode.Open,