备注：
Demo项目创建的控制器为.NET Core3.1框架
1、控制台应用程序代码
using System;
using System.IO;
namespace Excel_Import
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("开始执行导入Excel程序");
var filePath = @"D:\Test\TestExcel.xlsx";
using (FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
{
byte[] bytes = new byte[fileStream.Length];
fileStream.Read(bytes, 0, bytes.Length);
fileStream.Close();
// 把 byte[] 转换成 Stream
Stream stream = new MemoryStream(bytes);
var list = ExcelConvert.ToEntityStreamList<TestExcel>(stream, "TestExcel.xlsx");
Console.WriteLine("开始遍历TestExcel");
foreach (var item in list)
{
Console.WriteLine($"姓名：{item.Name}；地址：{item.Address}");
}
Console.WriteLine("遍历TestExcel结束");
Console.ReadLine();
}
}
}
/// <summary>
/// 测试Excel模型
/// </summary>
public class TestExcel
{
/// <summary>
/// 姓名
/// </summary>
[ExcelColumn("姓名")]
public string Name {
get; set; }
/// <summary>
/// 分组
/// </summary>
[ExcelColumn("地址")]
public string Address {
get; set; }
}
}
2、帮助类代码
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
using NPOI.XSSF.UserModel;
using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
namespace Excel_Import
{
/// <summary>
/// Excel帮助类
/// </summary>
public class ExcelConvert
{
public static List<T> ToEntityStreamList<T>(Stream stream, string fileName, bool firstRow2Name = true) where T : new()
{
return ToEntityList<T>(stream, fileName);
}
/// <summary>
/// Excel转换为实体列表【普通】
/// </summary>
/// <typeparam name="T">实体类</typeparam>
/// <param name="fileInfo">文件信息</param>
/// <param name="firstRow2Name">第一行是否做为列名,默认为true</param>
/// <returns></returns>
private static List<T> ToEntityList<T>(Stream stream, string fileName, bool firstRow2Name = true)
where T : new()
{
// 加载Excel
IWorkbook workbook;
try
{
// 格式判断
if (fileName.EndsWith(".xlsx"))
{
workbook = new XSSFWorkbook(stream);
}
else
{
workbook = new HSSFWorkbook(stream);
}
// 返回实体集
var entities = new List<T>();
// 读取第一页
ISheet sheet = workbook.GetSheetAt(0);
// 遍历所有行
IEnumerator rows = sheet.GetRowEnumerator();
// 反射实体判断实体行
var columns = new List<EntityColumn>();
#region 反射实体判断实体行对应Excel文件列
// 名称行
var excelFirstRow = new List<string>();
if (firstRow2Name && rows.MoveNext())
{
var row = (IRow)rows.Current;
for (int i = 0; i <= row.LastCellNum; i++)
{
ICell cell = row.GetCell(i);
if (cell == null) excelFirstRow.Add("");
else excelFirstRow.Add(cell.ToString());
}
}
// 反射
PropertyInfo[] propertys = typeof(T).GetProperties();
int propertyIndex = 0;
foreach (PropertyInfo property in propertys)
{
object[] excelColumns = property.GetCustomAttributes(typeof(ExcelColumnAttribute), true);
if (excelColumns.Length > 0)
{
string like = (excelColumns[0] as ExcelColumnAttribute).DisplayNameLike;
int excelIndex = (excelColumns[0] as ExcelColumnAttribute).ExcelIndex;
if (!string.IsNullOrEmpty(like))
{
for (int index = 0; index < excelFirstRow.Count; index++)
{
if (excelFirstRow[index].Contains(like))
{
columns.Add(new EntityColumn {
ColumnName = property.Name, ExcelIndex = index });
break;
}
}
}
else if (excelIndex > -1)
{
columns.Add(new EntityColumn {
ColumnName = property.Name, ExcelIndex = excelIndex });
}
else
{
columns.Add(new EntityColumn {
ColumnName = property.Name, ExcelIndex = propertyIndex });
}
}
propertyIndex++;
}
#endregion
// 遍历数据行
while (rows.MoveNext())
{
var row = (IRow)rows.Current;
var entity = new T();
PropertyInfo[] items = entity.GetType().GetProperties();
foreach (PropertyInfo property in items)
{
EntityColumn column = columns.FirstOrDefault(t => t.ColumnName == property.Name);
if (column != null)
{
ICell cell = row.GetCell(column.ExcelIndex);
if (cell == null)
//if (column.ExcelIndex - row.FirstCellNum >= row.Cells.Count || column.ExcelIndex - row.FirstCellNum < 0)
{
continue;
}
Object val = cell.ToString();
#region 数据类型转换
if (property.PropertyType == typeof(DateTime))
{
if (cell.CellType == CellType.Numeric)
{
val = cell.DateCellValue;
}
else
{
DateTime d;
DateTime.TryParse(val.ToString(), out d);
val = d;
}
}
else if (property.PropertyType == typeof(string))
{
val = val.ToString().Trim();
}
if (property.PropertyType == typeof(Int32))
{
if (cell.CellType == CellType.Numeric)
{
val = (int)Math.Round(cell.NumericCellValue);
}
Int32 d;
Int32.TryParse(val.ToString(), out d);
val = d;
}
else if (property.PropertyType == typeof(UInt32))
{
if (cell.CellType == CellType.Numeric)
{
val = Math.Round(cell.NumericCellValue);
}
UInt32 d;
UInt32.TryParse(val.ToString(), out d);
val = d;
}
else if (property.PropertyType == typeof(Int16))
{
if (cell.CellType == CellType.Numeric)
{
val = Math.Round(cell.NumericCellValue);
}
Int16 d;
Int16.TryParse(val.ToString(), out d);
val = d;
}
else if (property.PropertyType == typeof(UInt16))
{
if (cell.CellType == CellType.Numeric)
{
val = Math.Round(cell.NumericCellValue);
}
UInt16 d;
UInt16.TryParse(val.ToString(), out d);
val = d;
}
else if (property.PropertyType == typeof(float))
{
if (cell.CellType == CellType.Numeric)
{
val = cell.NumericCellValue;
}
float d;
float.TryParse(val.ToString(), out d);
val = d;
}
else if (property.PropertyType == typeof(decimal))
{
if (cell.CellType == CellType.Numeric)
{
val = cell.NumericCellValue;
}
decimal d;
decimal.TryParse(val.ToString(), out d);
val = d;
}
else if (property.PropertyType == typeof(double))
{
if (cell.CellType == CellType.Numeric)
{
val = cell.NumericCellValue;
}
else
{
double d;
double.TryParse(val.ToString(), out d);
val = d;
}
}
else if (property.PropertyType == typeof(byte))
{
if (cell.CellType == CellType.Numeric)
{
val = (byte)Convert.ToInt32(cell.NumericCellValue);
}
else
{
double d;
double.TryParse(val.ToString(), out d);
val = (byte)d;
}
}
#endregion
property.SetValue(entity, val, null);
}
}
entities.Add(entity);
}
// 返回结果
return entities;
}
catch (Exception ex)
{
}
return null;
}
private class EntityColumn
{
public string ColumnName {
get; set; }
public int ExcelIndex {
get; set; }
}
}
/// <summary>
/// Excel列属性【添加标签对象】
/// </summary>
public class ExcelColumnAttribute : Attribute
{
public ExcelColumnAttribute()
{
ExcelIndex = -1;
}
public ExcelColumnAttribute(int excelIndex)
{
ExcelIndex = excelIndex;
}
public ExcelColumnAttribute(string displayNameLike)
{
DisplayNameLike = displayNameLike;
}
public int ExcelIndex {
get; set; }
public string DisplayNameLike {
get; set; }
}
}
结果：
Excel说明：
首行必须和定义类（TestExcel）中的标签名一致
