C# excel导入导出，NOPI ，简单例子
C# 发现用NOPI 来对excel文件的导入导出，比较方便实用：
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Utility;
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
namespace AloneSell
{
public class ExcelFile
{
//引用方法：选中项目，右键-管理NuGet程序包,搜索npoi，安装npoi
#region Excel导入
///
/// Excel导入:读取excel文档数据到DataTable
///
/// excel文档路径
/// 要读取的工作表索引,为空=0
///
public DataTable Excel_Import(string path,int? isheet)
{
DataTable dt = new DataTable();
using (FileStream fsRead = new FileStream(path, FileMode.Open, FileAccess.Read))
{
#region
string extension = Path.GetExtension(path).ToLower();
IWorkbook workbook;
if (extension == ".xlsx")
{
workbook = new XSSFWorkbook(fsRead);
}
else
{
workbook = new HSSFWorkbook(fsRead);
}
if (isheet == null) { isheet = 0; }
ISheet sheet = workbook.GetSheetAt((int)isheet);
IRow currentRow = sheet.GetRow(0);
//最后一个方格的编号 即总的列数
int cellCount = currentRow.LastCellNum;
for (int i = 0; i < cellCount; i++)
{
//DataColumn dc = new DataColumn();
dt.Columns.Add(currentRow.GetCell(i).ToString());//增加列
}
#endregion
for (int j = 0; j <= sheet.LastRowNum - 1; j++)
{
dt.Rows.Add();//增加行
IRow currentRow1 = sheet.GetRow(j + 1);
if (currentRow1 != null)
{
#region
for (int c = 0; c < currentRow1.LastCellNum; c++)
{
ICell cell = currentRow1.GetCell(c);
if (cell == null || cell.CellType == CellType.Blank)
{
dt.Rows[j][c] = DBNull.Value;
}
else
{
//如果当前单元格不为空，则根据单元格的类型获取数据
switch (cell.CellType)
{
//只有当单元格的数据类型是数字类型的时候使用cell.NumericCellValue来获取值。其余类型都使用字符串来获取.日期类型数据插入单元格后也是CellType.NUMERIC
case CellType.Numeric:
//cell.NumericCellValue;
dt.Rows[j][c] = cell.NumericCellValue;
break;
default:
//cell.ToString();
dt.Rows[j][c] = cell.ToString();
break;
}
}
}
#endregion
}
}
workbook.Close();
return dt;
}
#region 例子
/*
try
{
OpenFileDialog openFile = new OpenFileDialog();
openFile.Filter = "excel2003|*.xls|excel|*.xlsx";
openFile.InitialDirectory = Application.StartupPath;
if (openFile.ShowDialog() == DialogResult.OK)
{
string fileName = openFile.FileName;
ExcelFile _excel = new ExcelFile();
DataTable table = _excel.Excel_Import(fileName,0);
//将数据存储到数据库中...
Pub.ShowInfo("导入excel数据成功");
}
}
catch (Exception ex)
{
Pub.ShowInfo(ex.Message);
}
*/
#endregion
}
#endregion
#region Excel导出
///
/// 导出到excel文档中
///
/// 数据源:DataGridView、DataTable
/// excel文档路径
/// 保存数据的工作表名
///
public int Excel_Export(object source, string path,string sheetName)
{
#region 判断数据源
DataGridView dgv = null;
DataTable table = null;
int iDataType = 0;//数据源格式：0=DataGridView;1=DataTable;
if (source is DataGridView)
{
dgv = (DataGridView)source;
iDataType = 0;
if (dgv.Rows.Count < 1)
{
Message = "要导出的数据为空，无法导出";
return -2;
}
}
else if (source is DataTable)
{
table = (DataTable)source;
iDataType = 1;
if (table == null || table.Rows.Count < 1)
{
Message = "要导出的数据为空，无法导出";
return -2;
}
}
else if (source is DataSet)
{
DataSet ds = ((DataSet)source);
if (ds == null || ds.Tables.Count < 1 || ds.Tables[0].Rows.Count < 1)
{
Message = "要导出的数据为空，无法导出";
return -2;
}
table = ds.Tables[0];
iDataType = 1;
}
else
{
Message = "导出失败,数据源source只支持DataTabel,DataGridView";
return -1;
}
#endregion
#region 导出excel
string extension = Path.GetExtension(path).ToLower();
IWorkbook workbook;
if (extension == ".xlsx")
{
workbook = new XSSFWorkbook();
}
else
{
workbook = new HSSFWorkbook();
}
sheetName = sheetName.Trim() == "" ? "sheet1" : sheetName;
ISheet sheet = workbook.CreateSheet(sheetName);
using (FileStream fs = new FileStream(path, FileMode.Create, FileAccess.ReadWrite))
{
IRow row_Head = sheet.CreateRow(0);
if (iDataType == 0)
{
#region 数据源是DataGridView
int icellIndex = 0;
for (int i = 0; i < dgv.Columns.Count; i++)
{
if (!dgv.Columns[i].Visible)
{
continue;
}
ICell cell = row_Head.CreateCell(icellIndex);
icellIndex++;
cell.SetCellValue(dgv.Columns[i].HeaderText);
}
for (int i = 0; i < dgv.Rows.Count; i++)
{
icellIndex = 0;
IRow row1 = sheet.CreateRow(i + 1);
for (int j = 0; j < dgv.Columns.Count; j++)
{
if (!dgv.Columns[j].Visible)
{
continue;
}
ICell cell = row1.CreateCell(icellIndex);
icellIndex++;
if (dgv.Rows[i].Cells[j].Value == null)
cell.SetCellValue("");
else
cell.SetCellValue(dgv.Rows[i].Cells[j].Value.ToString().Trim());
}
}
#endregion
}
else
{
#region 数据源是DataTable
for (int i = 0; i < table.Columns.Count; i++)
{
ICell cell = row_Head.CreateCell(i);
cell.SetCellValue(table.Columns[i].ColumnName);
}
for (int i = 0; i < table.Rows.Count; i++)
{
IRow row1 = sheet.CreateRow(i + 1);
for (int j = 0; j < table.Columns.Count; j++)
{
ICell cell = row1.CreateCell(j);
if (table.Rows[i][j] == null)
cell.SetCellValue("");
else
cell.SetCellValue(table.Rows[i][j].ToString().Trim());
}
}
#endregion
}
workbook.Write(fs);
workbook.Close();
}
#endregion
Message = "成功将数据导出到 " + path;
return 1;
#region 例子
/*
//可以先判断数据源，是否有数据
..........................
//导出Excel
SaveFileDialog saveFileDialog1 = new SaveFileDialog();
saveFileDialog1.DefaultExt = "xls";
saveFileDialog1.Filter = "excel2003|*.xls|excel|*.xlsx";
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
if (saveFileDialog1.FileName != "")
{
try
{
//1 = 成功；其他 = getCode(return)
//DataTable table = (DataTable)dataGridView1.DataSource;
ExcelFile _excel = new ExcelFile();
int iexcel = _excel.Excel_Export(dataGridView1, saveFileDialog1.FileName);//table
if (iexcel == 1)
Pub.ShowInfo("成功将数据导出到" + saveFileDialog1.FileName);
else
Pub.ShowInfo(_excel.getCode(iexcel));
}
catch (Exception ex)
{ Pub.ShowWarning(ex.Message); }
}
}
*/
#endregion
}
#endregion
public string getCode(int iCode)
{
string msg = "导出数据成功";
switch(iCode)
{
case -2:
{
msg = "要导出的数据为空，无法导出";
break;
}
case -1:
{
msg = "导出失败,数据源source只支持DataTabel,DataGridView";
break;
}
default:
{
break;
}
}
return msg;
}
#region 为了兼容原来的方法,实际还是兼容不了
///
/// 为了兼容原来的方法
///
///
///
public void DataGridViewToExcel(object source,string fileName)
{
Excel_Export(source, fileName, "");
}
///
/// 为了兼容原来的方法
///
///
///
public void DataGridViewToExcel(object source, string fileName,string sheetName)
{
Excel_Export(source, fileName, sheetName);
}
public delegate void MessageChange(string msg);
public event MessageChange OnMessageChange;
private string _Message = "";
public string Message
{
get { return _Message; }
set
{
_Message = value;
if (OnMessageChange != null)
{
OnMessageChange(value);
}
}
}
#endregion
}
}