C#中NPOI操作excel之读取和写入excel数据

一、下载引用

下载需要引用的dll，即：NPOI.dll，NPOI.OOXML.dll，NPOI.OpenXml4Net.dll，ICSharpCode.SharpZipLib.dll（office2007版需要此dll）。

二、excel转datatable类

1. using System;
2. using System.Data;
3. using System.IO;
4. using NPOI.SS.UserModel;
5. using NPOI.XSSF.UserModel;
6. using NPOI.HSSF.UserModel;
8. namespace NPOIOprateExcel
9. {
10. public class ExcelUtility
11. {
12. /// <summary>
13. /// 将excel导入到datatable
14. /// </summary>
15. /// <param name="filePath">excel路径</param>
16. /// <param name="isColumnName">第一行是否是列名</param>
17. /// <returns>返回datatable</returns>
18. public static DataTable ExcelToDataTable(string filePath, bool isColumnName)
19. {
20. DataTable dataTable = null;
21. FileStream fs = null;
22. DataColumn column = null;
23. DataRow dataRow = null;
24. IWorkbook workbook = null;
25. ISheet sheet = null;
26. IRow row = null;
27. ICell cell = null;
28. int startRow = 0;
29. try
30. {
31. using (fs = File.OpenRead(filePath))
32. {
33. // 2007版本
34. if (filePath.IndexOf(".xlsx") > 0)
35. workbook = new XSSFWorkbook(fs);
36. // 2003版本
37. else if (filePath.IndexOf(".xls") > 0)
38. workbook = new HSSFWorkbook(fs);
40. if (workbook != null)
41. {
42. sheet = workbook.GetSheetAt(0);//读取第一个sheet，当然也可以循环读取每个sheet
43. dataTable = new DataTable();
44. if (sheet != null)
45. {
46. int rowCount = sheet.LastRowNum;//总行数
47. if (rowCount > 0)
48. {
49. IRow firstRow = sheet.GetRow(0);//第一行
50. int cellCount = firstRow.LastCellNum;//列数
52. //构建datatable的列
53. if (isColumnName)
54. {
55. startRow = 1;//如果第一行是列名，则从第二行开始读取
56. for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
57. {
58. cell = firstRow.GetCell(i);
59. if (cell != null)
60. {
61. if (cell.StringCellValue != null)
62. {
63. column = new DataColumn(cell.StringCellValue);
64. dataTable.Columns.Add(column);
65. }
66. }
67. }
68. }
69. else
70. {
71. for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
72. {
73. column = new DataColumn("column" + (i + 1));
74. dataTable.Columns.Add(column);
75. }
76. }
78. //填充行
79. for (int i = startRow; i <= rowCount; ++i)
80. {
81. row = sheet.GetRow(i);
82. if (row == null) continue;
84. dataRow = dataTable.NewRow();
85. for (int j = row.FirstCellNum; j < cellCount; ++j)
86. {
87. cell = row.GetCell(j);
88. if (cell == null)
89. {
90. dataRow[j] = "";
91. }
92. else
93. {
94. //CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,)
95. switch (cell.CellType)
96. {
97. case CellType.Blank:
98. dataRow[j] = "";
99. break;
100. case CellType.Numeric:
101. short format = cell.CellStyle.DataFormat;
102. //对时间格式（2015.12.5、2015/12/5、2015-12-5等）的处理
103. if (format == 14 || format == 31 || format == 57 || format == 58)
104. dataRow[j] = cell.DateCellValue;
105. else
106. dataRow[j] = cell.NumericCellValue;
107. break;
108. case CellType.String:
109. dataRow[j] = cell.StringCellValue;
110. break;
111. }
112. }
113. }
114. dataTable.Rows.Add(dataRow);
115. }
116. }
117. }
118. }
119. }
120. return dataTable;
121. }
122. catch (Exception)
123. {
124. if (fs != null)
125. {
126. fs.Close();
127. }
128. return null;
129. }
130. }
131. }
132. }

三、结果

四、写入excel类

1. public static bool DataTableToExcel(DataTable dt)
2. {
3. bool result = false;
4. IWorkbook workbook = null;
5. FileStream fs = null;
6. IRow row = null;
7. ISheet sheet = null;
8. ICell cell = null;
9. try
10. {
11. if (dt != null && dt.Rows.Count > 0)
12. {
13. workbook = new HSSFWorkbook();
14. sheet = workbook.CreateSheet("Sheet0");//创建一个名称为Sheet0的表
15. int rowCount = dt.Rows.Count;//行数
16. int columnCount = dt.Columns.Count;//列数
18. //设置列头
19. row = sheet.CreateRow(0);//excel第一行设为列头
20. for (int c = 0; c < columnCount; c++)
21. {
22. cell = row.CreateCell(c);
23. cell.SetCellValue(dt.Columns[c].ColumnName);
24. }
26. //设置每行每列的单元格,
27. for (int i = 0; i <rowCount; i++)
28. {
29. row = sheet.CreateRow(i+1);
30. for (int j = 0; j < columnCount; j++)
31. {
32. cell = row.CreateCell(j);//excel第二行开始写入数据
33. cell.SetCellValue(dt.Rows[i][j].ToString());
34. }
35. }
36. using (fs = File.OpenWrite(@"D:/myxls.xls"))
37. {
38. workbook.Write(fs);//向打开的这个xls文件中写入数据
39. result = true;
40. }
41. }
42. return result;
43. }
44. catch (Exception ex)
45. {
46. if (fs != null)
47. {
48. fs.Close();
49. }
50. return false;
51. }
52. }

文章来源: C#中NPOI操作excel之读取和写入excel数据