使用的NPOI

1. nuget  Npoi

 

代码如下

/// <summary>
/// 将excel导入到datatable
/// </summary>
/// <param name="filePath">excel路径</param>
/// <param name="isColumnName">第一行是否是列名</param>
/// <returns>返回datatable</returns>
public static DataTable ExcelToDataTable(string filePath, bool isColumnName)
{
DataTable dataTable = null;
FileStream fs = null;
DataColumn column = null;
DataRow dataRow = null;
IWorkbook workbook = null;
ISheet sheet = null;
IRow row = null;
ICell cell = null;
int startRow = 0;

using (fs = File.OpenRead(filePath))
{
if (filePath.IndexOf(".xlsx") > 0)// 2007版本
{
workbook = new XSSFWorkbook(fs);
}
else if (filePath.IndexOf(".xls") > 0)// 2003版本
{
workbook = new HSSFWorkbook(fs);
}

if (workbook != null)
{
sheet = workbook.GetSheetAt(0);//读取第一个sheet，当然也可以循环读取每个sheet
dataTable = new DataTable();
if (sheet != null)
{
int rowCount = sheet.LastRowNum;//总行数
if (rowCount > 0)
{
IRow firstRow = sheet.GetRow(0);//第一行
int cellCount = firstRow.LastCellNum;//列数

//构建datatable的列
if (isColumnName)
{
startRow = 1;//如果第一行是列名，则从第二行开始读取
for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
{
cell = firstRow.GetCell(i);
if (cell == null)
{
break;
}
if (cell.StringCellValue != null)
{
column = new DataColumn(cell.StringCellValue);
dataTable.Columns.Add(column);
}
}
}
else
{
for (int i = firstRow.FirstCellNum; i < cellCount; ++i)
{
column = new DataColumn("column" + (i + 1));
dataTable.Columns.Add(column);
}
}

//填充行
for (int i = startRow; i <= rowCount; ++i)
{
row = sheet.GetRow(i);
if (row == null)
{
break;
}
dataRow = dataTable.NewRow();
for (int j = row.FirstCellNum; j < cellCount; ++j)
{
cell = row.GetCell(j);
ICell Test = row.GetCell(3);
if (cell == null)
{
dataRow[j] = "";
}
else
{
switch (cell.CellType)
{
case CellType.Blank:
dataRow[j] = "";
break;
case CellType.Numeric:
short format = cell.CellStyle.DataFormat;
//对时间格式（2015.12.5、2015/12/5、2015-12-5等）的处理
if (format == 14 || format == 31 || format == 57 || format == 58)
{
dataRow[j] = cell.DateCellValue;
}
else if (format == 20) //对时间格式HH:mm
{
dataRow[j] = cell.DateCellValue.TimeOfDay.ToString();
}
else
dataRow[j] = cell.NumericCellValue;
break;
case CellType.String:
dataRow[j] = cell.StringCellValue;
break;
}
}
}
dataTable.Rows.Add(dataRow);
}
}
}
}
}
return dataTable;

}

}

需要注意的是文件的后缀名  xls 是2003及之前的版本 xlsx是2007及之后的版本 还有xlsm 看的资料说的带宏嵌了代码的（这个好像转换不了？） 

 

很奇怪 网上查了问多DataFormat对应的值的文档 只查到下面关于时间的

所有日期格式都可以通过getDataFormat()值来判断

yyyy-MM-dd----- 14

yyyy年m月d日--- 31

yyyy年m月------- 57

m月d日 ---------- 58

HH:mm----------- 20

h时mm分 ------- 32