，使用NPOI导入Excel
首先在MVC项目中导入NPOI
查询NPOI安装，排序依据，选择：最高下载量，选择第一个。
在控制器中创建ExcelController
在Index视图中写入代码：
@using (Html.BeginForm("Import", "Excel", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
<input name="file" type="file" id="=file" />
<input name="submit" id="submit" type="submit" value="批量导入" />
}
创建Import控制器
添加Import视图
Import控制器中的代码：
[HttpPost]
public ActionResult Import(HttpPostedFileBase file)
{
var fileName = file.FileName;
var filePath = Server.MapPath(string.Format("~/{0}", "Files"));
string path = Path.Combine(filePath, fileName);
file.SaveAs(path);
DataTable excelTable = new DataTable();
excelTable = ImportExcel.GetExcelDataTable(path);
DataTable dbdata = new DataTable();
dbdata.Columns.Add("email");
dbdata.Columns.Add("pwd");
dbdata.Columns.Add("logintime");
for (int i = 0; i < excelTable.Rows.Count; i++)
{
DataRow dr = excelTable.Rows[i];
DataRow dr_ = dbdata.NewRow();
dr_["email"] = dr["邮箱"];
dr_["pwd"] = dr["密码"];
dr_["logintime"] = dr["时间"];
dbdata.Rows.Add(dr_);
}
RemoveEmpty(dbdata);
string constr = System.Configuration.ConfigurationManager.AppSettings["meixinEntities_"];
SqlBulkCopyByDatatable(constr, "m_user1", dbdata);
return View();
}
添加logic文档，添加ImportExcel类
这里需要引用NPOI类库，ImportExcel类里的代码：
using NPOI;
using System.Data;
using NPOI.SS.UserModel;
using System.IO;
using NPOI.HSSF.UserModel;
using NPOI.XSSF.UserModel;
namespace MvcExcel导入导出1.logic
{
public class ImportExcel
{
public static DataTable GetExcelDataTable(string filePath)
{
IWorkbook Workbook;
DataTable table = new DataTable();
try
{
using (FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
//XSSFWorkbook 适用XLSX格式，HSSFWorkbook 适用XLS格式
string fileExt = Path.GetExtension(filePath).ToLower();
if (fileExt == ".xls")
{
Workbook = new HSSFWorkbook(fileStream);
}
else if (fileExt == ".xlsx")
{
Workbook = new XSSFWorkbook(fileStream);
}
else
{
Workbook = null;
}
}
}
catch (Exception ex)
{
throw ex;
}
//定位在第一个sheet
ISheet sheet = Workbook.GetSheetAt(0);
//第一行为标题行
IRow headerRow = sheet.GetRow(0);
int cellCount = headerRow.LastCellNum;
int rowCount = sheet.LastRowNum;
//循环添加标题列
for (int i = headerRow.FirstCellNum; i < cellCount; i++)
{
DataColumn column = new DataColumn(headerRow.GetCell(i).StringCellValue);
table.Columns.Add(column);
}
//数据
for (int i = (sheet.FirstRowNum + 1); i <= rowCount; i++)
{
IRow row = sheet.GetRow(i);
DataRow dataRow = table.NewRow();
if (row != null)
{
for (int j = row.FirstCellNum; j < cellCount; j++)
{
if (row.GetCell(j) != null)
{
dataRow[j] = GetCellValue(row.GetCell(j));
}
}
}
table.Rows.Add(dataRow);
}
return table;
}
private static string GetCellValue(ICell cell)
{
if (cell == null)
{
return string.Empty;
}
switch (cell.CellType)
{
case CellType.Blank:
return string.Empty;
case CellType.Boolean:
return cell.BooleanCellValue.ToString();
case CellType.Error:
return cell.ErrorCellValue.ToString();
case CellType.Numeric:
case CellType.Unknown:
default:
return cell.ToString();
case CellType.String:
return cell.StringCellValue;
case CellType.Formula:
try
{
HSSFFormulaEvaluator e = new HSSFFormulaEvaluator(cell.Sheet.Workbook);
e.EvaluateInCell(cell);
return cell.ToString();
}
catch
{
return cell.NumericCellValue.ToString();
}
}
}
在Import控制器中获取到datatable的数据之后，在下面添加批量插入DataTable数据的方法，传入三个参数。
/// <summary>
/// 大数据插入
/// </summary>
/// <param name="connectionString">目标库连接</param>
/// <param name="TableName">目标表</param>
/// <param name="dtSelect">来源数据</param>
public static void SqlBulkCopyByDatatable(string connectionString, string TableName, DataTable dtSelect)
{
using (SqlConnection conn = new SqlConnection(connectionString))
{
using (SqlBulkCopy sqlbulkcopy = new SqlBulkCopy(connectionString, SqlBulkCopyOptions.UseInternalTransaction))
{
try
{
sqlbulkcopy.DestinationTableName = TableName;
sqlbulkcopy.BatchSize = 20000;
sqlbulkcopy.BulkCopyTimeout = 0;//不限时间
for (int i = 0; i < dtSelect.Columns.Count; i++)
{
sqlbulkcopy.ColumnMappings.Add(dtSelect.Columns[i].ColumnName, dtSelect.Columns[i].ColumnName);
}
sqlbulkcopy.WriteToServer(dtSelect);
}
catch (System.Exception ex)
{
throw ex;
}
}
}
}
第一个是从NPOI读取到的Excel的数据，保存到excelTable里，第二个是把表的中文表头转换成数据库表中对应的英文，第三个是获取连接字符串，调用批量插入数据库的方法
插入数据需要传入数据库连接字符串，在Web.config中的<appSettings>中添加自己的数据库连接字符串
在导入Excel数据的时候，有时候会有空行，用RemoveEmpty方法去空，代码如下
protected void RemoveEmpty(DataTable dt)
{
List<DataRow> removelist = new List<DataRow>();
for (int i = 0; i < dt.Rows.Count; i++)
{
bool IsNull = true;
for (int j = 0; j < dt.Columns.Count; j++)
{
if (!string.IsNullOrEmpty(dt.Rows[i][j].ToString().Trim()))
{
IsNull = false;
}
}
if (IsNull)
{
removelist.Add(dt.Rows[i]);
}
}
for (int i = 0; i < removelist.Count; i++)
{
dt.Rows.Remove(removelist[i]);
}
}