Excel导入导出在开发中是非常常见的,对Excel操作,NPOI使用的是最常用的,但单单用NPOI,要写得代码还是比较多的,可以借助一个Npoi.Mapper库,操作起来就非常简单了,十来行代码就可以对Excel和List互相转换,非常简便。
首先NuGet引入NPOI和Npoi.Mapper
增加一个ExcelHelper
public class ExcelHelper { /// <summary> /// List转Excel /// </summary> /// <typeparam name="T"></typeparam> /// <param name="list">数据</param> /// <param name="sheetName">表名</param> /// <param name="overwrite">true,覆盖单元格,false追加内容(list和创建的excel或excel模板)</param> /// <param name="xlsx">true-xlsx,false-xls</param> /// <returns>返回文件</returns> public static MemoryStream ParseListToExcel<T>(List<T> list, string sheetName = "sheet1", bool overwrite = true, bool xlsx = true) where T : class { var mapper = new Mapper(); MemoryStream ms = new MemoryStream(); mapper.Save<T>(ms, list, sheetName, overwrite, xlsx); return ms; } /// <summary> /// Excel转为List /// </summary> /// <typeparam name="T"></typeparam> /// <param name="fileStream"></param> /// <param name="sheetname"></param> /// <returns></returns> public static List<T> ParseExcelToList<T>(Stream fileStream, string sheetname = "") where T : class { List<T> ModelList = new List<T>(); var mapper = new Mapper(fileStream); List<RowInfo<T>> DataList = new List<RowInfo<T>>(); if (!string.IsNullOrEmpty(sheetname)) { DataList = mapper.Take<T>(sheetname).ToList(); } else { DataList = mapper.Take<T>().ToList(); } if (DataList != null && DataList.Count > 0) { foreach (var item in DataList) { ModelList.Add(item.Value); } } return ModelList; } }
1. 增加一个User Model用作导出,Column指明导出时表头显示的列名
public class User { [Column("用户ID")] public int UserId { get; set; } [Column("用户名")] public string UserName { get; set; } [Column("手机号")] public string Phone { get; set; } [Column("邮箱")] public string Email { get; set; } }
增加一个FileController控制器
public class FileController : Controller { public IActionResult Index() { return View(); } [HttpPost] public IActionResult Upload() { //用户List List<User> users = new List<User>(); //获取到上传的文件 var file = Request.Form.Files[0]; //文件转成流 using (var fileStream = file.OpenReadStream()) { //excel转实体 users = ExcelHelper.ParseExcelToList<User>(fileStream, "Sheet1"); } return Content(JsonConvert.SerializeObject(users)); } public IActionResult DownLoad() { //生成List List<User> usrs = new List<User>(); for(int i=1;i<=10;i++) { User user = new User() { UserId = i, UserName = "用户" + i, Phone = "13800000000", Email = $"user{i}@qq.com" }; usrs.Add(user); } //List转为Excel文件 var fileStream = ExcelHelper.ParseListToExcel(usrs); return File(fileStream.ToArray(), "application/vnd.ms-excel", "用户信息.xlsx"); } }
Index的视图
@{ } <a href="/File/DownLoad">导出excel文件</a> <form action="/File/Upload" method="post" enctype="multipart/form-data" > 选择excel文件: <input type="file" name="file" /> <input type="submit" value="上传excel" /> </form>
打开导出的文件,内容正是生成的列表信息
可以看到刚才的excel已经转换为User的集合了
这个组件操作Excel和Model的互相转换非常简单快捷,推荐使用。
源码地址:https://github.com/weixiaolong325/ExcelDemo