一、下載引用
目前官網不能直接下載到引用的dll，需要自己打包（我沒有自己打包，我有現成的DLL，地址：https://files.cnblogs.com/files/dengxixi/NPOIdll.7z），即：NPOI.dll，NPOI.OOXML.dll，NPOI.OpenXml4Net.dll，ICSharpCode.SharpZipLib.dll。（解壓密碼是：123456）
二、創建MVC項目，頁面代碼：
<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>使用NPOI導入excel</title>
<script src="Scripts/jquery-1.8.2.min.js"></script>
<style>
.myFileUpload {
position: absolute;
display: block;
width: 100px;
height: 40px;
opacity: 0;
}
</style>
</head>
<body>
<div class="container">
<form class="form-horizontal" action="~/Home/Upload" role="form" method="post" enctype="multipart/form-data">
<table style="margin:5px;height:70px;">
<tr>
<td>請選擇文件：</td>
<td width="5px;"></td>
<td><input type="file" id="fileUpload" name="fileUpload"></td>
<td><input id="fileText" type="text" class="myFileUpload" disabled="disabled" /></td>
<td><button type="submit">上傳</button></td>
</tr>
</table>
</form>
</div>
</body>
</html>
三、EXCEL轉為為datatable類，網上百度的，改了下，因為沒有判斷excel的版本
public class ExcelHelper { /// <summary>讀取excel 到datatable /// 默認第一行為表頭，導入第一個工作表 /// </summary> /// <param name="strFileName">excel文檔路徑</param> /// <returns></returns> public static DataTable ExcelToDataTable(string strFileName) { DataTable dt = new DataTable(); FileStream file = null; IWorkbook Workbook = null; try { using (file = new FileStream(strFileName, FileMode.Open, FileAccess.Read))//C#文件流讀取文件 { if (strFileName.IndexOf(".xlsx") > 0) //把xlsx文件中的數據寫入Workbook中 Workbook = new XSSFWorkbook(file); else if (strFileName.IndexOf(".xls") > 0) //把xls文件中的數據寫入Workbook中 Workbook = new HSSFWorkbook(file); if (Workbook != null) { ISheet sheet = Workbook.GetSheetAt(0);//讀取第一個sheet System.Collections.IEnumerator rows = sheet.GetRowEnumerator(); //得到Excel工作表的行 IRow headerRow = sheet.GetRow(0); //得到Excel工作表的總列數 int cellCount = headerRow.LastCellNum; for (int j = 0; j < cellCount; j++) { //得到Excel工作表指定行的單元格 ICell cell = headerRow.GetCell(j); dt.Columns.Add(cell.ToString()); } for (int i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++) { IRow row = sheet.GetRow(i); DataRow dataRow = dt.NewRow(); for (int j = row.FirstCellNum; j < cellCount; j++) { if (row.GetCell(j) != null) dataRow[j] = row.GetCell(j).ToString(); } dt.Rows.Add(dataRow); } } return dt; } } catch (Exception) { if (file != null) { file.Close();//關閉當前流並釋放資源 } return null; } } /// <summary> /// 從Excel中獲取數據到DataTable /// </summary> /// <param name="strFileName">Excel文件全路徑(服務器路徑)</param> /// <param name="SheetName">要獲取數據的工作表名稱</param> /// <param name="HeaderRowIndex">工作表標題行所在行號(從0開始)</param> /// <returns></returns> public static DataTable RenderDataTableFromExcel(string strFileName, string SheetName, int HeaderRowIndex) { IWorkbook Workbook = null; using (FileStream file = new FileStream(strFileName, FileMode.Open, FileAccess.Read)) { if (strFileName.IndexOf(".xlsx") > 0) Workbook = new XSSFWorkbook(file); else if (strFileName.IndexOf(".xls") > 0) Workbook = new HSSFWorkbook(file); ISheet sheet = Workbook.GetSheet(SheetName); return RenderDataTableFromExcel(Workbook, SheetName, HeaderRowIndex); } } /// <summary> /// 從Excel中獲取數據到DataTable /// </summary> /// <param name="workbook">要處理的工作薄</param> /// <param name="SheetName">要獲取數據的工作表名稱</param> /// <param name="HeaderRowIndex">工作表標題行所在行號(從0開始)</param> /// <returns></returns> public static DataTable RenderDataTableFromExcel(IWorkbook workbook, string SheetName, int HeaderRowIndex) { ISheet sheet = workbook.GetSheet(SheetName); DataTable table = new DataTable(); try { IRow headerRow = sheet.GetRow(HeaderRowIndex); int cellCount = headerRow.LastCellNum; for (int i = headerRow.FirstCellNum; i < cellCount; i++) { DataColumn column = new DataColumn(headerRow.GetCell(i).StringCellValue); table.Columns.Add(column); } int rowCount = sheet.LastRowNum; #region 循環各行各列,寫入數據到DataTable for (int i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++) { IRow row = sheet.GetRow(i); DataRow dataRow = table.NewRow(); for (int j = row.FirstCellNum; j < cellCount; j++) { ICell cell = row.GetCell(j); if (cell == null) { dataRow[j] = null; } else { //dataRow[j] = cell.ToString(); switch (cell.CellType) { case CellType.Blank: dataRow[j] = null; break; case CellType.Boolean: dataRow[j] = cell.BooleanCellValue; break; case CellType.Numeric: dataRow[j] = cell.ToString(); break; case CellType.String: dataRow[j] = cell.StringCellValue; break; case CellType.Error: dataRow[j] = cell.ErrorCellValue; break; case CellType.Formula: default: dataRow[j] = "=" + cell.CellFormula; break; } } } table.Rows.Add(dataRow); //dataRow[j] = row.GetCell(j).ToString(); } #endregion } catch (System.Exception ex) { table.Clear(); table.Columns.Clear(); table.Columns.Add("出錯了"); DataRow dr = table.NewRow(); dr[0] = ex.Message; table.Rows.Add(dr); return table; } finally { //sheet.Dispose(); workbook = null; sheet = null; } #region 清除最后的空行 for (int i = table.Rows.Count - 1; i > 0; i--) { bool isnull = true; for (int j = 0; j < table.Columns.Count; j++) { if (table.Rows[i][j] != null) { if (table.Rows[i][j].ToString() != "") { isnull = false; break; } } } if (isnull) { table.Rows[i].Delete(); } } #endregion return table; } }
四、調用方法
public string Upload(HttpPostedFileBase fileUpload) { if (fileUpload == null) { return "文件為空"; } try { //將硬盤路徑轉化為服務器路徑的文件流 string fileName = Path.Combine(Request.MapPath("~/SaveFile"), Path.GetFileName(fileUpload.FileName)); //NPOI得到EXCEL的第一種方法 fileUpload.SaveAs(fileName); DataTable dtData = ExcelHelper.ExcelToDataTable(fileName); //得到EXCEL的第二種方法(第一個參數是文件流,第二個是excel標簽名,第三個是第幾行開始讀0算第一行) DataTable dtData2 = ExcelHelper.RenderDataTableFromExcel(fileName, fileUpload.FileName, 0); return "導入成功"; } catch { return "導入失敗"; } }
五、調試截圖及excel 數據截圖：
以上就是把excel轉化為datatable的方法。轉化為datatable之后就可以進行插入數據庫或者顯示到頁面了。