版权声明：本文为博主原创文章，未经博主允许不得转载。

using System;
using System.Data;
using System.IO;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using NPOI.HSSF.UserModel;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
class ExcelHelper
{
/// <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>
/// <param name="textBox">检查所用</param>
/// <returns>返回datatable</returns>
public static DataTable ExcelToDataTable(string filePath, bool isColumnName,TextBox textBox)
{
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 = 9;
try
{
using (fs = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
// 2010版本
if (filePath.IndexOf(".xlsx") > 0)
workbook = new XSSFWorkbook(fs);
// 2003版本
else if (filePath.IndexOf(".xls") > 0)
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(1);//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)
{
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) continue;
int sign = 0;//用于计数
dataRow = dataTable.NewRow();
for (int j = row.FirstCellNum; j < cellCount; ++j)
{
if (j == -1)//超过有内容的行数后，会出现此种情况
break;
if (!sheet.IsColumnHidden(j))//判断是否为隐藏行
{
cell = row.GetCell(j);
if (cell == null)
{
dataRow[sign] = "";
}
else
{
//CellType(Unknown = -1,Numeric = 0,String = 1,Formula = 2,Blank = 3,Boolean = 4,Error = 5,)
switch (cell.CellType)
{
case CellType.Blank:
dataRow[sign] = "";
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[sign] = cell.DateCellValue;
else
dataRow[sign] = cell.NumericCellValue;
break;
case CellType.String:
dataRow[sign] = cell.StringCellValue;
break;
}
}
sign++;
}
}
dataTable.Rows.Add(dataRow);
}
}
}
}
}
return dataTable;
}
catch (Exception ex)
{
System.Windows.Forms.MessageBox.Show(ex.ToString());
if (fs != null)
{
fs.Close();
}
return null;
}
}

}
}

用NPOI将excel内容导出，忽略合并列的类容