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(1)OleDB方法
長處:將Excel直接當作數據源處置,經由過程SQL直接讀取內容,讀取速度較快。
缺陷:讀取數據方法不敷靈巧,沒法直接讀取某一個單位格,只要將全部Sheet頁讀掏出來後(成果為Datatable)再在Datatable中依據行列數來獲得指定的值。
當Excel數據量很年夜時。會異常占用內存,當內存不敷時會拋出內存溢出的異常。
讀代替碼以下:
public DataTable GetExcelTableByOleDB(string strExcelPath, string tableName) { try { DataTable dtExcel = new DataTable(); //數據表 DataSet ds = new DataSet(); //獲得文件擴大名 string strExtension = System.IO.Path.GetExtension(strExcelPath); string strFileName = System.IO.Path.GetFileName(strExcelPath); //Excel的銜接 OleDbConnection objConn = null; switch (strExtension) { case ".xls": objConn = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + strExcelPath + ";" + "Extended Properties=\"Excel 8.0;HDR=NO;IMEX=1;\""); break; case ".xlsx": objConn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + strExcelPath + ";" + "Extended Properties=\"Excel 12.0;HDR=NO;IMEX=1;\""); break; default: objConn = null; break; } if (objConn == null) { return null; } objConn.Open(); //獲得Excel中一切Sheet表的信息 //System.Data.DataTable schemaTable = objConn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables, null); //獲得Excel的第一個Sheet表名 //string tableName = schemaTable.Rows[0][2].ToString().Trim(); string strSql = "select * from [" + tableName + "]"; //獲得Excel指定Sheet表中的信息 OleDbCommand objCmd = new OleDbCommand(strSql, objConn); OleDbDataAdapter myData = new OleDbDataAdapter(strSql, objConn); myData.Fill(ds, tableName);//填湊數據 objConn.Close(); //dtExcel即為excel文件中指定表中存儲的信息 dtExcel = ds.Tables[tableName]; return dtExcel; } catch { return null; } }
上面解釋一下銜接字符串
HDR=Yes,這代表第一行是題目,不做為數據應用(然則我在現實應用中,假如第一行存在龐雜數值,那末讀獲得到的Datatable列題目會主動設置為F1、F2等方法定名,與現實運用不符,所以其時是經由過程HDR=No方法將一切內容讀取到Datatable中,然背工動將第一行設置成題目的);IMEX ( IMport EXport mode )設置
IMEX 有三種形式:
0 is Export mode
1 is Import mode
2 is Linked mode (full update capabilities)
我這裡特殊要解釋的就是 IMEX 參數了,由於分歧的形式代表著分歧的讀寫行動:
當 IMEX=0 時為“匯出形式”,這個形式開啟的 Excel 檔案只能用來做“寫入”用處。
當 IMEX=1 時為“匯入形式”,這個形式開啟的 Excel 檔案只能用來做“讀取”用處。
當 IMEX=2 時為“鏈接形式”,這個形式開啟的 Excel 檔案可同時增援“讀取”與“寫入”用處。
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別的,讀取Excel2007版本的文件時,版本應當從8.0改成12.0,同時驅動不克不及再用Jet,而應當用ACE。擔任會形成“找不到可裝置的 ISAM”的毛病。
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在網上還發明采取這類方法存在掏出的Sheet表的個數多於現實Excel表中的Sheet表個數的情形,其緣由有二:
1. 掏出的稱號中,包含了XL定名治理器中的稱號(拜見XL2007的公式--定名治理器, 快捷鍵Crtl+F3);
2. 掏出的稱號中,包含了FilterDatabase後綴的, 這是XL用來記載Filter規模的。
關於第一點比擬簡略, 刪除已有定名治理器中的內容便可;第二點處置起來比擬費事, Filter刪除後這些稱號仍然保存著,簡略的做法是新增Sheet然後將原Sheet Copy出來。但現實情形其實不能為每一個Excel做以上檢討。上面給出了過濾的計劃。(此成績我們有驗證過,年夜家本身驗證一下吧)
//objConn為讀取Excel的鏈接,上面經由過程過濾來獲得有用的Sheet頁稱號聚集 System.Data.DataTable schemaTable = objConn.GetOleDbSchemaTable(System.Data.OleDb.OleDbSchemaGuid.Tables, null); List<string> lstSheetNames = new List<string>(); for (int i = 0; i < schemaTable.Rows.Count; i++) { string strSheetName = (string)dtSheetName.Rows[i]["TABLE_NAME"]; if (strSheetName.Contains("$") && !strSheetName.WordStr("'", "").EndsWith("$")) { //過濾有效SheetName終了.... continue; } if (lstSheetNames != null && !lstSheetNames.Contains(strSheetName)) lstSheetNames.Add(strSheetName); }
由於讀掏出來有效SheetName普通情形最初一個字符都不會是$。假如SheetName有一些特別符號,讀掏出來的SheetName會主動加上單引號。好比在Excel中將SheetName編纂成MySheet(1),此時讀掏出來的SheetName就為:'MySheet(1)$',所以斷定最初一個字符是否是$之前最好過濾一下單引號。
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(2)Com組件的方法(經由過程添加 Microsoft.Office.Interop.Excel援用完成)
長處:可以或許異常靈巧的讀取Excel中的數據,用戶可以靈巧的挪用各類函數停止處置。
缺陷:基於單位格的處置,讀取速度較慢,關於數據量較年夜的文件最好不要應用此種方法讀取。
須要添加響應的DLL援用,必需存在此援用才可以使用,假如是Web站點安排在IIS上時,還須要辦事器機子已裝置了Excel,有時刻還須要為設置裝備擺設IIS權限。
讀代替碼以下:
private Stopwatch wath = new Stopwatch(); /// <summary> /// 應用COM讀取Excel /// </summary> /// <param name="excelFilePath">途徑</param> /// <returns>DataTabel</returns> public System.Data.DataTable GetExcelData(string excelFilePath) { Excel.Application app = new Excel.Application(); Excel.Sheets sheets; Excel.Workbook workbook = null; object oMissiong = System.Reflection.Missing.Value; System.Data.DataTable dt = new System.Data.DataTable(); wath.Start(); try { if (app == null) { return null; } workbook = app.Workbooks.Open(excelFilePath, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong); //將數據讀入到DataTable中——Start sheets = workbook.Worksheets; Excel.Worksheet worksheet = (Excel.Worksheet)sheets.get_Item(1);//讀取第一張表 if (worksheet == null) return null; string cellContent; int iRowCount = worksheet.UsedRange.Rows.Count; int iColCount = worksheet.UsedRange.Columns.Count; Excel.Range range; //擔任列頭Start DataColumn dc; int ColumnID = 1; range = (Excel.Range)worksheet.Cells[1, 1]; while (range.Text.ToString().Trim() != "") { dc = new DataColumn(); dc.DataType = System.Type.GetType("System.String"); dc.ColumnName = range.Text.ToString().Trim(); dt.Columns.Add(dc); range = (Excel.Range)worksheet.Cells[1, ++ColumnID]; } //End for (int iRow = 2; iRow <= iRowCount; iRow++) { DataRow dr = dt.NewRow(); for (int iCol = 1; iCol <= iColCount; iCol++) { range = (Excel.Range)worksheet.Cells[iRow, iCol]; cellContent = (range.Value2 == null) ? "" : range.Text.ToString(); dr[iCol - 1] = cellContent; } dt.Rows.Add(dr); } wath.Stop(); TimeSpan ts = wath.Elapsed; //將數據讀入到DataTable中——End return dt; } catch { return null; } finally { workbook.Close(false, oMissiong, oMissiong); System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook); workbook = null; app.Workbooks.Close(); app.Quit(); System.Runtime.InteropServices.Marshal.ReleaseComObject(app); app = null; GC.Collect(); GC.WaitForPendingFinalizers(); } } /// <summary> /// 應用COM,多線程讀取Excel(1 主線程、4 副線程) /// </summary> /// <param name="excelFilePath">途徑</param> /// <returns>DataTabel</returns> public System.Data.DataTable ThreadReadExcel(string excelFilePath) { Excel.Application app = new Excel.Application(); Excel.Sheets sheets = null; Excel.Workbook workbook = null; object oMissiong = System.Reflection.Missing.Value; System.Data.DataTable dt = new System.Data.DataTable(); wath.Start(); try { if (app == null) { return null; } workbook = app.Workbooks.Open(excelFilePath, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong, oMissiong); //將數據讀入到DataTable中——Start sheets = workbook.Worksheets; Excel.Worksheet worksheet = (Excel.Worksheet)sheets.get_Item(1);//讀取第一張表 if (worksheet == null) return null; string cellContent; int iRowCount = worksheet.UsedRange.Rows.Count; int iColCount = worksheet.UsedRange.Columns.Count; Excel.Range range; //擔任列頭Start DataColumn dc; int ColumnID = 1; range = (Excel.Range)worksheet.Cells[1, 1]; while (iColCount >= ColumnID) { dc = new DataColumn(); dc.DataType = System.Type.GetType("System.String"); string strNewColumnName = range.Text.ToString().Trim(); if (strNewColumnName.Length == 0) strNewColumnName = "_1"; //斷定列名能否反復 for (int i = 1; i < ColumnID; i++) { if (dt.Columns[i - 1].ColumnName == strNewColumnName) strNewColumnName = strNewColumnName + "_1"; } dc.ColumnName = strNewColumnName; dt.Columns.Add(dc); range = (Excel.Range)worksheet.Cells[1, ++ColumnID]; } //End //數據年夜於500條,應用多過程停止讀取數據 if (iRowCount - 1 > 500) { //開端多線程讀取數據 //新建線程 int b2 = (iRowCount - 1) / 10; DataTable dt1 = new DataTable("dt1"); dt1 = dt.Clone(); SheetOptions sheet1thread = new SheetOptions(worksheet, iColCount, 2, b2 + 1, dt1); Thread othread1 = new Thread(new ThreadStart(sheet1thread.SheetToDataTable)); othread1.Start(); //壅塞 1 毫秒,包管第一個讀取 dt1 Thread.Sleep(1); DataTable dt2 = new DataTable("dt2"); dt2 = dt.Clone(); SheetOptions sheet2thread = new SheetOptions(worksheet, iColCount, b2 + 2, b2 * 2 + 1, dt2); Thread othread2 = new Thread(new ThreadStart(sheet2thread.SheetToDataTable)); othread2.Start(); DataTable dt3 = new DataTable("dt3"); dt3 = dt.Clone(); SheetOptions sheet3thread = new SheetOptions(worksheet, iColCount, b2 * 2 + 2, b2 * 3 + 1, dt3); Thread othread3 = new Thread(new ThreadStart(sheet3thread.SheetToDataTable)); othread3.Start(); DataTable dt4 = new DataTable("dt4"); dt4 = dt.Clone(); SheetOptions sheet4thread = new SheetOptions(worksheet, iColCount, b2 * 3 + 2, b2 * 4 + 1, dt4); Thread othread4 = new Thread(new ThreadStart(sheet4thread.SheetToDataTable)); othread4.Start(); //主線程讀取殘剩數據 for (int iRow = b2 * 4 + 2; iRow <= iRowCount; iRow++) { DataRow dr = dt.NewRow(); for (int iCol = 1; iCol <= iColCount; iCol++) { range = (Excel.Range)worksheet.Cells[iRow, iCol]; cellContent = (range.Value2 == null) ? "" : range.Text.ToString(); dr[iCol - 1] = cellContent; } dt.Rows.Add(dr); } othread1.Join(); othread2.Join(); othread3.Join(); othread4.Join(); //將多個線程讀掏出來的數據追加至 dt1 前面 foreach (DataRow dr in dt.Rows) dt1.Rows.Add(dr.ItemArray); dt.Clear(); dt.Dispose(); foreach (DataRow dr in dt2.Rows) dt1.Rows.Add(dr.ItemArray); dt2.Clear(); dt2.Dispose(); foreach (DataRow dr in dt3.Rows) dt1.Rows.Add(dr.ItemArray); dt3.Clear(); dt3.Dispose(); foreach (DataRow dr in dt4.Rows) dt1.Rows.Add(dr.ItemArray); dt4.Clear(); dt4.Dispose(); return dt1; } else { for (int iRow = 2; iRow <= iRowCount; iRow++) { DataRow dr = dt.NewRow(); for (int iCol = 1; iCol <= iColCount; iCol++) { range = (Excel.Range)worksheet.Cells[iRow, iCol]; cellContent = (range.Value2 == null) ? "" : range.Text.ToString(); dr[iCol - 1] = cellContent; } dt.Rows.Add(dr); } } wath.Stop(); TimeSpan ts = wath.Elapsed; //將數據讀入到DataTable中——End return dt; } catch { return null; } finally { workbook.Close(false, oMissiong, oMissiong); System.Runtime.InteropServices.Marshal.ReleaseComObject(workbook); System.Runtime.InteropServices.Marshal.ReleaseComObject(sheets); workbook = null; app.Workbooks.Close(); app.Quit(); System.Runtime.InteropServices.Marshal.ReleaseComObject(app); app = null; GC.Collect(); GC.WaitForPendingFinalizers(); } }
(3)NPOI方法讀取Excel(此辦法未經由測試)
NPOI 是 POI 項目標 .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。應用 NPOI 你便可以在沒有裝置 Office 或許響應情況的機械上對 WORD/EXCEL 文檔停止讀寫。
長處:讀取Excel速度較快,讀取方法操作靈巧性
缺陷:須要下載響應的插件並添加到體系援用傍邊。
/// <summary> /// 將excel中的數據導入到DataTable中 /// </summary> /// <param name="sheetName">excel任務薄sheet的稱號</param> /// <param name="isFirstRowColumn">第一行能否是DataTable的列名</param> /// <returns>前往的DataTable</returns> public DataTable ExcelToDataTable(string sheetName, bool isFirstRowColumn) { ISheet sheet = null; DataTable data = new DataTable(); int startRow = 0; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); if (fileName.IndexOf(".xlsx") > 0) // 2007版本 workbook = new XSSFWorkbook(fs); else if (fileName.IndexOf(".xls") > 0) // 2003版本 workbook = new HSSFWorkbook(fs); if (sheetName != null) { sheet = workbook.GetSheet(sheetName); } else { sheet = workbook.GetSheetAt(0); } if (sheet != null) { IRow firstRow = sheet.GetRow(0); int cellCount = firstRow.LastCellNum; //一行最初一個cell的編號 即總的列數 if (isFirstRowColumn) { for (int i = firstRow.FirstCellNum; i < cellCount; ++i) { DataColumn column = new DataColumn(firstRow.GetCell(i).StringCellValue); data.Columns.Add(column); } startRow = sheet.FirstRowNum + 1; } else { startRow = sheet.FirstRowNum; } //最初一列的標號 int rowCount = sheet.LastRowNum; for (int i = startRow; i <= rowCount; ++i) { IRow row = sheet.GetRow(i); if (row == null) continue; //沒稀有據的行默許是null DataRow dataRow = data.NewRow(); for (int j = row.FirstCellNum; j < cellCount; ++j) { if (row.GetCell(j) != null) //同理,沒稀有據的單位格都默許是null dataRow[j] = row.GetCell(j).ToString(); } data.Rows.Add(dataRow); } } return data; } catch (Exception ex) { Console.WriteLine("Exception: " + ex.Message); return null; } }
上面是一些相干的文章,年夜家可以參考下