【推荐】.NET使用NPOI组件将数据导出Excel

1、NPOI官方网站：http://npoi.codeplex.com/

   可以到此网站上去下载最新的NPOI组件版本

2、NPOI在线学习教程（中文版）：

    http://www.cnblogs.com/tonyqus/archive/2009/04/12/1434209.html

   感谢Tony Qu分享出NPOI组件的使用方法

3、.NET调用NPOI组件导入导出Excel的操作类
　　此NPOI操作类的优点如下：
   （1）支持web及winform从DataTable导出到Excel； 
   （2）生成速度很快； 
   （3）准确判断数据类型，不会出现身份证转数值等问题； 
   （4）如果单页条数大于65535时会新建工作表； 
   （5）列宽自适应；

  1 using System;
  2 using System.Data;
  3 using System.Configuration;
  4 using System.Web;
  5 using System.Web.Security;
  6 using System.Web.UI;
  7 using System.Web.UI.HtmlControls;
  8 using System.Web.UI.WebControls;
  9 using System.Web.UI.WebControls.WebParts;
 10 using System.IO;
 11 using System.Text;
 12 using NPOI;
 13 using NPOI.HPSF;
 14 using NPOI.HSSF;
 15 using NPOI.HSSF.UserModel;
 16 using NPOI.HSSF.Util;
 17 using NPOI.POIFS;
 18 using NPOI.Util;  
 20 namespace PMS.Common
 21 {
 22     public class NPOIHelper
 23     {
 24         /// <summary>
 25         /// DataTable导出到Excel文件
 26         /// </summary>
 27         /// <param name="dtSource">源DataTable</param>
 28         /// <param name="strHeaderText">表头文本</param>
 29         /// <param name="strFileName">保存位置</param>
 30         public static void Export(DataTable dtSource, string strHeaderText, string strFileName)
 31         {
 32             using (MemoryStream ms = Export(dtSource, strHeaderText))
 33             {
 34                 using (FileStream fs = new FileStream(strFileName, FileMode.Create, FileAccess.Write))
 35                 {
 36                     byte[] data = ms.ToArray();
 37                     fs.Write(data, 0, data.Length);
 38                     fs.Flush();
 39                 }
 40             }
 41         }
 42 
 43         /// <summary>
 44         /// DataTable导出到Excel的MemoryStream
 45         /// </summary>
 46         /// <param name="dtSource">源DataTable</param>
 47         /// <param name="strHeaderText">表头文本</param>
 48         public static MemoryStream Export(DataTable dtSource, string strHeaderText)
 49         {
 50             HSSFWorkbook workbook = new HSSFWorkbook();
 51             HSSFSheet sheet = workbook.CreateSheet();
 52 
 53             #region 右击文件 属性信息
 54             {
 55                 DocumentSummaryInformation dsi = PropertySetFactory.CreateDocumentSummaryInformation();
 56                 dsi.Company = "NPOI";
 57                 workbook.DocumentSummaryInformation = dsi;
 58 
 59                 SummaryInformation si = PropertySetFactory.CreateSummaryInformation();
 60                 si.Author = "文件作者信息"; //填加xls文件作者信息
 61                 si.ApplicationName = "创建程序信息"; //填加xls文件创建程序信息
 62                 si.LastAuthor = "最后保存者信息"; //填加xls文件最后保存者信息
 63                 si.Comments = "作者信息"; //填加xls文件作者信息
 64                 si.Title = "标题信息"; //填加xls文件标题信息
 65                 si.Subject = "主题信息";//填加文件主题信息
 66                 si.CreateDateTime = DateTime.Now;
 67                 workbook.SummaryInformation = si;
 68             }
 69             #endregion
 70 
 71             HSSFCellStyle dateStyle = workbook.CreateCellStyle();
 72             HSSFDataFormat format = workbook.CreateDataFormat();
 73             dateStyle.DataFormat = format.GetFormat("yyyy-mm-dd");
 74 
 75             //取得列宽
 76             int[] arrColWidth = new int[dtSource.Columns.Count];
 77             foreach (DataColumn item in dtSource.Columns)
 78             {
 79                 arrColWidth[item.Ordinal] = Encoding.GetEncoding(936).GetBytes(item.ColumnName.ToString()).Length;
 80             }
 81             for (int i = 0; i < dtSource.Rows.Count; i++)
 82             {
 83                 for (int j = 0; j < dtSource.Columns.Count; j++)
 84                 {
 85                     int intTemp = Encoding.GetEncoding(936).GetBytes(dtSource.Rows[i][j].ToString()).Length;
 86                     if (intTemp > arrColWidth[j])
 87                     {
 88                         arrColWidth[j] = intTemp;
 89                     }
 90                 }
 91             } 
 95             int rowIndex = 0; 
 97             foreach (DataRow row in dtSource.Rows)
 98             {
 99                 #region 新建表，填充表头，填充列头，样式
100                 if (rowIndex == 65535 || rowIndex == 0)
101                 {
102                     if (rowIndex != 0)
103                     {
104                         sheet = workbook.CreateSheet();
105                     }
106 
107                     #region 表头及样式
108                     {
109                         HSSFRow headerRow = sheet.CreateRow(0);
110                         headerRow.HeightInPoints = 25;
111                         headerRow.CreateCell(0).SetCellValue(strHeaderText);
112 
113                         HSSFCellStyle headStyle = workbook.CreateCellStyle();
114                         headStyle.Alignment = CellHorizontalAlignment.CENTER;
115                         HSSFFont font = workbook.CreateFont();
116                         font.FontHeightInPoints = 20;
117                         font.Boldweight = 700;
118                         headStyle.SetFont(font);
119                         headerRow.GetCell(0).CellStyle = headStyle;
120                         sheet.AddMergedRegion(new Region(0, 0, 0, dtSource.Columns.Count - 1));
121                         headerRow.Dispose();
122                     }
123                     #endregion
124 
125 
126                     #region 列头及样式
127                     {
128                         HSSFRow headerRow = sheet.CreateRow(1); 
131                         HSSFCellStyle headStyle = workbook.CreateCellStyle();
132                         headStyle.Alignment = CellHorizontalAlignment.CENTER;
133                         HSSFFont font = workbook.CreateFont();
134                         font.FontHeightInPoints = 10;
135                         font.Boldweight = 700;
136                         headStyle.SetFont(font); 
139                         foreach (DataColumn column in dtSource.Columns)
140                         {
141                             headerRow.CreateCell(column.Ordinal).SetCellValue(column.ColumnName);
142                             headerRow.GetCell(column.Ordinal).CellStyle = headStyle;
143 
144                             //设置列宽
145                             sheet.SetColumnWidth(column.Ordinal, (arrColWidth[column.Ordinal] + 1) * 256); 
147                         }
148                         headerRow.Dispose();
149                     }
150                     #endregion
151 
152                     rowIndex = 2;
153                 }
154                 #endregion
155 
156 
157                 #region 填充内容
158                 HSSFRow dataRow = sheet.CreateRow(rowIndex);
159                 foreach (DataColumn column in dtSource.Columns)
160                 {
161                     HSSFCell newCell = dataRow.CreateCell(column.Ordinal);
162 
163                     string drValue = row[column].ToString();
164 
165                     switch (column.DataType.ToString())
166                     {
167                         case "System.String"://字符串类型
168                             newCell.SetCellValue(drValue);
169                             break;
170                         case "System.DateTime"://日期类型
171                             DateTime dateV;
172                             DateTime.TryParse(drValue, out dateV);
173                             newCell.SetCellValue(dateV);
174 
175                             newCell.CellStyle = dateStyle;//格式化显示
176                             break;
177                         case "System.Boolean"://布尔型
178                             bool boolV = false;
179                             bool.TryParse(drValue, out boolV);
180                             newCell.SetCellValue(boolV);
181                             break;
182                         case "System.Int16"://整型
183                         case "System.Int32":
184                         case "System.Int64":
185                         case "System.Byte":
186                             int intV = 0;
187                             int.TryParse(drValue, out intV);
188                             newCell.SetCellValue(intV);
189                             break;
190                         case "System.Decimal"://浮点型
191                         case "System.Double":
192                             double doubV = 0;
193                             double.TryParse(drValue, out doubV);
194                             newCell.SetCellValue(doubV);
195                             break;
196                         case "System.DBNull"://空值处理
197                             newCell.SetCellValue("");
198                             break;
199                         default:
200                             newCell.SetCellValue("");
201                             break;
202                     }
203 
204                 }
205                 #endregion
206 
207                 rowIndex++;
208             } 
211             using (MemoryStream ms = new MemoryStream())
212             {
213                 workbook.Write(ms);
214                 ms.Flush();
215                 ms.Position = 0;
216 
217                 sheet.Dispose();
218                 //workbook.Dispose();//一般只用写这一个就OK了，他会遍历并释放所有资源，但当前版本有问题所以只释放sheet
219                 return ms;
220             } 
222         }
223 
224         /// <summary>
225         /// 用于Web导出
226         /// </summary>
227         /// <param name="dtSource">源DataTable</param>
228         /// <param name="strHeaderText">表头文本</param>
229         /// <param name="strFileName">文件名</param>
230         public static void ExportByWeb(DataTable dtSource, string strHeaderText, string strFileName)
231         { 
233             HttpContext curContext = HttpContext.Current;
234 
235             // 设置编码和附件格式
236             curContext.Response.ContentType = "application/vnd.ms-excel";
237             curContext.Response.ContentEncoding = Encoding.UTF8;
238             curContext.Response.Charset = "";
239             curContext.Response.AppendHeader("Content-Disposition",
240                 "attachment;filename=" + HttpUtility.UrlEncode(strFileName, Encoding.UTF8));
241 
242             curContext.Response.BinaryWrite(Export(dtSource, strHeaderText).GetBuffer());
243             curContext.Response.End(); 
245         } 
247 
248         /// <summary>读取excel
249         /// 默认第一行为标头
250         /// </summary>
251         /// <param name="strFileName">excel文档路径</param>
252         /// <returns></returns>
253         public static DataTable Import(string strFileName)
254         {
255             DataTable dt = new DataTable();
256 
257             HSSFWorkbook hssfworkbook;
258             using (FileStream file = new FileStream(strFileName, FileMode.Open, FileAccess.Read))
259             {
260                 hssfworkbook = new HSSFWorkbook(file);
261             }
262             HSSFSheet sheet = hssfworkbook.GetSheetAt(0);
263             System.Collections.IEnumerator rows = sheet.GetRowEnumerator();
264 
265             HSSFRow headerRow = sheet.GetRow(0);
266             int cellCount = headerRow.LastCellNum;
267 
268             for (int j = 0; j < cellCount; j++)
269             {
270                 HSSFCell cell = headerRow.GetCell(j);
271                 dt.Columns.Add(cell.ToString());
272             }
273 
274             for (int i = (sheet.FirstRowNum + 1); i <= sheet.LastRowNum; i++)
275             {
276                 HSSFRow row = sheet.GetRow(i);
277                 DataRow dataRow = dt.NewRow();
278 
279                 for (int j = row.FirstCellNum; j < cellCount; j++)
280                 {
281                     if (row.GetCell(j) != null)
282                         dataRow[j] = row.GetCell(j).ToString();
283                 }
284 
285                 dt.Rows.Add(dataRow);
286             }
287             return dt;
288         }
289     }
290 }
291 

4、NPOI操作类的调用方法
   DataTable dt_Grade = Tools.Data.GetDataTable(strSQL);
   filename += "绩效考核结果分数统计表";
   PMS.Common.NPOIHelper.ExportByWeb(dt_Grade, filename, filename+".xls");

5、效果展示
   

6、NPOI类库下载：https://files.cnblogs.com/dreamof/NPOI类库.rar

信息来源：http://www.cnblogs.com/yongfa365/archive/2010/05/10/NPOI-MyXls-DataTable-To-Excel-From-Excel.html