NPOI

  1   public class ExcelOperator
  2     {
  3         /// <summary>
  4         /// Init Workbook
  5         /// </summary>
  6         /// <param name="path">excel file path</param>
  7         /// <returns></returns>
  8         private IWorkbook InitializeWorkbook(string path)
  9         {
 10             string extension = Path.GetExtension(path);
 11             if (string.IsNullOrEmpty(extension) ||
 12                 (
 13                  !".xlsx".Equals(extension.ToLower()) &&
 14                  !".xls".Equals(extension.ToLower())
 15                 )
 16                )
 17             {
 18                 throw new InvalidOperationException("this is not a excel file");
 19             }
 20 
 21             IWorkbook workbook;
 22 
 23             if (".xlsx".Equals(extension.ToLower()))
 24             {
 25                 workbook = new XSSFWorkbook();
 26             }
 27             else
 28             {
 29                 workbook = new HSSFWorkbook();
 30             }
 31 
 32             return workbook;
 33         }
 34 
 35         /// <summary>
 36         /// Init Workbook
 37         /// </summary>
 38         /// <param name="path">excel file path</param>
 39         /// <param name="fileStream"></param>
 40         /// <returns></returns>
 41         private IWorkbook InitializeWorkbook(string path, out FileStream fileStream)
 42         {
 43             string extension = Path.GetExtension(path);
 44             if (string.IsNullOrEmpty(extension) ||
 45                 (
 46                  !".xlsx".Equals(extension.ToLower()) &&
 47                  !".xls".Equals(extension.ToLower())
 48                 )
 49                )
 50             {
 51                 throw new InvalidOperationException("this is not a excel file");
 52             }
 53 
 54             IWorkbook workbook;
 55             fileStream = new FileStream(path, FileMode.OpenOrCreate, FileAccess.ReadWrite);
 56 
 57             if (".xlsx".Equals(extension.ToLower()))
 58             {
 59                 workbook = new XSSFWorkbook(fileStream);
 60             }
 61             else
 62             {
 63                 workbook = new HSSFWorkbook(fileStream);
 64             }
 65 
 66             return workbook;
 67         }
 68 
 69         /// <summary>
 70         /// 将excel中的数据导入到DataTable中
 71         /// </summary>
 72         /// <param name="path">excel路径</param>
 73         /// <param name="sheetName">excel工作薄sheet的名称</param>
 74         /// <param name="isFirstRowColumn">第一行是否是DataTable的列名</param>
 75         /// <returns>返回的DataTable</returns>
 76         public DataTable ExcelToDataTable(string path, string sheetName, bool isFirstRowColumn)
 77         {
 78             FileStream fileStream = null;
 79 
 80             try
 81             {
 82                 DataTable data = new DataTable();
 83 
 84                 IWorkbook workbook = InitializeWorkbook(path, out fileStream);
 85 
 86                 //如果不指定sheet,则获取第一个sheet
 87                 ISheet sheet = sheetName != null ? workbook.GetSheet(sheetName) : workbook.GetSheetAt(0);
 88 
 89                 //check sheet是否存在
 90                 if (sheet == null)
 91                 {
 92                     throw new InvalidOperationException("Sheet does not exist");
 93                 }
 94 
 95                 IRow firstRow = sheet.GetRow(0);
 96                 int firstCellNum = firstRow.FirstCellNum;
 97                 int lastCellNum = firstRow.LastCellNum;
 98 
 99                 int startRow = 0;
100                 if (isFirstRowColumn)
101                 {
102                     //添加列
103                     for (int i = firstCellNum; i < lastCellNum; i++)
104                     {
105                         ICell cell = firstRow.GetCell(i);
106                         if (cell != null)
107                         {
108                             string cellValue = cell.StringCellValue;
109                             if (cellValue != null)
110                             {
111                                 var column = new DataColumn(cellValue);
112                                 data.Columns.Add(column);
113                             }
114                         }
115                     }
116                     startRow = sheet.FirstRowNum + 1;
117                 }
118                 else
119                 {
120                     startRow = sheet.FirstRowNum;
121                 }
122 
123                 //最后一列的标号
124                 int rowCount = sheet.LastRowNum;
125                 for (int i = startRow; i <= rowCount; i++)
126                 {
127                     IRow row = sheet.GetRow(i);
128                     if (row == null) continue;
129 
130                     DataRow dataRow = data.NewRow();
131                     for (int j = firstCellNum; j < lastCellNum; j++)
132                     {
133                         if (row.GetCell(j) != null)
134                             dataRow[j] = row.GetCell(j).ToString();
135                     }
136                     data.Rows.Add(dataRow);
137                 }
138 
139                 return data;
140             }
141             catch (Exception)
142             {
143                 throw;
144             }
145             finally
146             {
147                 if (fileStream != null) fileStream.Close();
148             }
149         }
150 
151         /// <summary>
152         /// 将DataTable数据导入到excel中
153         /// </summary>
154         /// <param name="data">要导入的数据</param>
155         /// <param name="sheetName">要导入的excel的sheet的名称</param>
156         /// <param name="isColumnWritten">DataTable的列名是否要导入</param>
157         /// <param name="path">要导入数据的excel路径</param>
158         /// <returns>导入数据行数(包含列名那一行)</returns>
159         public int DataTableToExcel(DataTable data, string sheetName, bool isColumnWritten, string path)
160         {
161             int count;
162 
163             IWorkbook workbook = InitializeWorkbook(path);
164 
165             if (string.IsNullOrEmpty(sheetName))
166             {
167                 sheetName = "Sheet1";
168             }
169 
170             ISheet sheet = workbook.CreateSheet(sheetName);
171             //写入DataTable的列名
172             if (isColumnWritten)
173             {
174                 IRow row = sheet.CreateRow(0);
175                 for (int j = 0; j < data.Columns.Count; ++j)
176                 {
177                     row.CreateCell(j).SetCellValue(data.Columns[j].ColumnName);
178                 }
179                 count = 1;
180             }
181             else
182             {
183                 count = 0;
184             }
185 
186             //写入行数据
187             for (int i = 0; i < data.Rows.Count; ++i)
188             {
189                 IRow row = sheet.CreateRow(count);
190                 for (int j = 0; j < data.Columns.Count; ++j)
191                 {
192                     row.CreateCell(j).SetCellValue(data.Rows[i][j].ToString());
193                 }
194                 count++;
195             }
196 
197             using (var fileStream = new FileStream(path, FileMode.OpenOrCreate, FileAccess.Write))
198             {
199                 workbook.Write(fileStream);
200             }
201 
202             return count;
203         }
204 
205     }