C#使用NOPI库实现导入Excel文档

时间:2022-01-12 17:35:37

使用NOPI导入Excel文档

NOPI版本:2.3.0,依赖于NPOI的SharpZipLib版本:0.86,经测试适用于.net4.0+

记录遇到的几个问题

1.NOPI中的IWorkbook接口:xls使用HSSFWorkbook类实现,xlsx使用XSSFWorkbook类实现

2.日期转换,判断row.GetCell(j).CellType == NPOI.SS.UserModel.CellType.Numeric && HSSFDateUtil.IsCellDateFormatted(row.GetCell(j)

不能直接使用row.GetCell(j).DateCellValue,这玩意会直接抛出异常来~

1. 将文件流转换为DataTable

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
/// <summary>
/// 根据Excel格式读取Excel
/// </summary>
/// <param name="stream">文件流</param>
/// <param name="type">Excel格式枚举类型,xls/xlsx</param>
/// <param name="sheetName">表名,默认取第一张</param>
/// <returns>DataTable</returns>
private static DataTable ImportExcel(Stream stream, ExcelExtType type, string sheetName)
{
  DataTable dt = new DataTable();
  IWorkbook workbook;
  try
  {
    //xls使用HSSFWorkbook类实现,xlsx使用XSSFWorkbook类实现
    switch (type)
    {
      case ExcelExtType.xlsx:
        workbook = new XSSFWorkbook(stream);
        break;
      default:
        workbook = new HSSFWorkbook(stream);
        break;
    }
    ISheet sheet = null;
    //获取工作表 默认取第一张
    if (string.IsNullOrWhiteSpace(sheetName))
      sheet = workbook.GetSheetAt(0);
    else
      sheet = workbook.GetSheet(sheetName);
 
    if (sheet == null)
      return null;
    IEnumerator rows = sheet.GetRowEnumerator();
    #region 获取表头
    IRow headerRow = sheet.GetRow(0);
    int cellCount = headerRow.LastCellNum;
    for (int j = 0; j < cellCount; j++)
    {
      ICell cell = headerRow.GetCell(j);
      if (cell != null)
      {
        dt.Columns.Add(cell.ToString());
      }
      else
      {
        dt.Columns.Add("");
      }
    }
    #endregion
    #region 获取内容
    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)
        {
          //判断单元格是否为日期格式
          if (row.GetCell(j).CellType == NPOI.SS.UserModel.CellType.Numeric && HSSFDateUtil.IsCellDateFormatted(row.GetCell(j)))
          {
            if (row.GetCell(j).DateCellValue.Year >=1970)
            {
              dataRow[j] = row.GetCell(j).DateCellValue.ToString();
            }
            else
            {
              dataRow[j] = row.GetCell(j).ToString();
 
            }
          }
          else
          {
            dataRow[j] = row.GetCell(j).ToString();
          }
        }
      }
      dt.Rows.Add(dataRow);
    }
    #endregion
 
  }
  catch (Exception ex)
  {
    dt=null;
  }
  finally
  {
    //if (stream != null)
    //{
    //  stream.Close();
    //  stream.Dispose();
    //}
  }
  return dt;
}

2. 文件上载导入

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
/// <summary>
/// 上传Excel导入
/// </summary>
/// <param name="file">上载文件对象</param>
/// <param name="errorMsg">错误信息</param>
/// <param name="sheetName">表名,默认取第一张</param>
/// <returns></returns>
public static DataTable Import(System.Web.HttpPostedFileBase file, ref string errorMsg, string sheetName = "")
{
  if (file == null || file.InputStream == null || file.InputStream.Length == 0)
  {
    errorMsg = "请选择要导入的Excel文件";
    return null;
  }
  var excelType = GetExcelFileType(file.FileName);
  if (excelType == null)
  {
    errorMsg = "请选择正确的Excel文件";
    return null;
  }
  using (var stream = new MemoryStream())
  {
    file.InputStream.Position = 0;
    file.InputStream.CopyTo(stream);
    var dt = ImportExcel(stream, excelType.Value, sheetName);
    if (dt == null)
      errorMsg = "导入失败,请选择正确的Excel文件";
    return dt;
  }
}

3. 本地路径读取导入
 

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
/// <summary>
/// 根据文件路径导入Excel
/// </summary>
/// <param name="filePath"></param>
/// <param name="errorMsg">错误信息</param>
/// <param name="sheetName">表名,默认取第一张</param>
/// <returns>可能为null的DataTable</returns>
public static DataTable Import(string filePath, ref string errorMsg, string sheetName = "")
{
  var excelType = GetExcelFileType(filePath);
  if (GetExcelFileType(filePath) == null)
  {
    errorMsg = "请选择正确的Excel文件";
    return null;
  }
  if (!File.Exists(filePath))
  {
    errorMsg = "没有找到要导入的Excel文件";
    return null;
  }
  DataTable dt;
  using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
  {
    dt = ImportExcel(stream, excelType.Value, sheetName);
  }
  if (dt == null)
    errorMsg = "导入失败,请选择正确的Excel文件";
  return dt;
}

4.完整demo

附赠一个winform导入Excel的Demo。

https://github.com/yimogit/NopiExcelDemo