C# NPOI读取Excel数据
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
namespace SYS_TEST.BaseClass
{
//NPOI方式
//NPOI 是 POI 项目的 .NET 版本。POI是一个开源的Java读写Excel、WORD等微软OLE2组件文档的项目。使用 NPOI 你就可以在没有安装 Office 或者相应环境的机器上对 WORD/EXCEL 文档进行读写。
//优点：读取Excel速度较快，读取方式操作灵活性
//缺点：需要下载相应的插件并添加到系统引用当中。
public class NPOIClass
{
/// <summary>
/// Excel转换成DataTable（.xls）
/// </summary>
/// <param name="filePath">Excel文件路径</param>
/// <returns></returns>
public static DataTable ExcelToDataTable(string filePath)
{
var dt = new DataTable();
using (var file = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
var hssfworkbook = new HSSFWorkbook(file);
var sheet = hssfworkbook.GetSheetAt(0);
for (var j = 0; j < 5; j++)
{
dt.Columns.Add(Convert.ToChar(((int)'A') + j).ToString());
}
var rows = sheet.GetRowEnumerator();
while (rows.MoveNext())
{
var row = (HSSFRow)rows.Current;
var dr = dt.NewRow();
for (var i = 0; i < row.LastCellNum; i++)
{
var cell = row.GetCell(i);
if (cell == null)
{
dr[i] = null;
}
else
{
switch (cell.CellType)
{
case CellType.Blank:
dr[i] = "[null]";
break;
case CellType.Boolean:
dr[i] = cell.BooleanCellValue;
break;
case CellType.Numeric:
dr[i] = cell.ToString();
break;
case CellType.String:
dr[i] = cell.StringCellValue;
break;
case CellType.Error:
dr[i] = cell.ErrorCellValue;
break;
case CellType.Formula:
try
{
dr[i] = cell.NumericCellValue;
}
catch
{
dr[i] = cell.StringCellValue;
}
break;
default:
dr[i] = "=" + cell.CellFormula;
break;
}
}
}
dt.Rows.Add(dr);
}
}
return dt;
}
/// <summary>
/// Excel转换成DataSet（.xlsx/.xls）
/// </summary>
/// <param name="filePath">Excel文件路径</param>
/// <param name="strMsg"></param>
/// <returns></returns>
public static DataSet ExcelToDataSet(string filePath, out string strMsg)
{
strMsg = "";
DataSet ds = new DataSet();
DataTable dt = new DataTable();
string fileType = Path.GetExtension(filePath).ToLower();
string fileName = Path.GetFileName(filePath).ToLower();
try
{
ISheet sheet = null;
int sheetNumber = 0;
FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read);
if (fileType == ".xlsx")
{
// 2007版本
XSSFWorkbook workbook = new XSSFWorkbook(fs);
sheetNumber = workbook.NumberOfSheets;
for (int i = 0; i < sheetNumber; i++)
{
string sheetName = workbook.GetSheetName(i);
sheet = workbook.GetSheet(sheetName);
if (sheet != null)
{
dt = GetSheetDataTable(sheet, out strMsg);
if (dt != null)
{
dt.TableName = sheetName.Trim();
ds.Tables.Add(dt);
}
else
{
MessageBox.Show("Sheet数据获取失败，原因：" + strMsg);
}
}
}
}
else if (fileType == ".xls")
{
// 2003版本
HSSFWorkbook workbook = new HSSFWorkbook(fs);
sheetNumber = workbook.NumberOfSheets;
for (int i = 0; i < sheetNumber; i++)
{
string sheetName = workbook.GetSheetName(i);
sheet = workbook.GetSheet(sheetName);
if (sheet != null)
{
dt = GetSheetDataTable(sheet, out strMsg);
if (dt != null)
{
dt.TableName = sheetName.Trim();
ds.Tables.Add(dt);
}
else
{
MessageBox.Show("Sheet数据获取失败，原因：" + strMsg);
}
}
}
}
return ds;
}
catch (Exception ex)
{
strMsg = ex.Message;
return null;
}
}
/// <summary>
/// 获取sheet表对应的DataTable
/// </summary>
/// <param name="sheet">Excel工作表</param>
/// <param name="strMsg"></param>
/// <returns></returns>
private static DataTable GetSheetDataTable(ISheet sheet, out string strMsg)
{
strMsg = "";
DataTable dt = new DataTable();
string sheetName = sheet.SheetName;
int startIndex = 0;// sheet.FirstRowNum;
int lastIndex = sheet.LastRowNum;
//最大列数
int cellCount = 0;
IRow maxRow = sheet.GetRow(0);
for (int i = startIndex; i <= lastIndex; i++)
{
IRow row = sheet.GetRow(i);
if (row != null && cellCount < row.LastCellNum)
{
cellCount = row.LastCellNum;
maxRow = row;
}
}
//列名设置
try
{
for (int i = 0; i < maxRow.LastCellNum; i++)//maxRow.FirstCellNum
{
dt.Columns.Add(Convert.ToChar(((int)'A') + i).ToString());
//DataColumn column = new DataColumn("Column" + (i + 1).ToString());
//dt.Columns.Add(column);
}
}
catch
{
strMsg = "工作表" + sheetName + "中无数据";
return null;
}
//数据填充
for (int i = startIndex; i <= lastIndex; i++)
{
IRow row = sheet.GetRow(i);
DataRow drNew = dt.NewRow();
if (row != null)
{
for (int j = row.FirstCellNum; j < row.LastCellNum; ++j)
{
if (row.GetCell(j) != null)
{
ICell cell = row.GetCell(j);
switch (cell.CellType)
{
case CellType.Blank:
drNew[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)
drNew[j] = cell.DateCellValue;
else
drNew[j] = cell.NumericCellValue;
if (cell.CellStyle.DataFormat == 177 || cell.CellStyle.DataFormat == 178 || cell.CellStyle.DataFormat == 188)
drNew[j] = cell.NumericCellValue.ToString("#0.00");
break;
case CellType.String:
drNew[j] = cell.StringCellValue;
break;
case CellType.Formula:
try
{
drNew[j] = cell.NumericCellValue;
if (cell.CellStyle.DataFormat == 177 || cell.CellStyle.DataFormat == 178 || cell.CellStyle.DataFormat == 188)
drNew[j] = cell.NumericCellValue.ToString("#0.00");
}
catch
{
try
{
drNew[j] = cell.StringCellValue;
}
catch { }
}
break;
default:
drNew[j] = cell.StringCellValue;
break;
}
}
}
}
dt.Rows.Add(drNew);
}
return dt;
}
}
}
