1、文件上传下载（MVC应用）
视图：form表单，编码方式为multipart/form-data
<body> ???<div> ????????<form action="/Demo/FileUpload" enctype="multipart/form-data" method="post"> ???????????<input id="f1" type="file" name="f1" /> ???????????<input id="Submit1" type="submit" value="上传" /> ???????</form> ???????<a href="/Demo/FileDownLoad">下载</a> ???</div></body>
控制器
public ActionResult FileUpLoad(HttpPostedFileBase f1) ???????{ ???????????string path = Server.MapPath("~/Picture"); ???????????string filename = Path.Combine(path,f1.FileName); ???????????f1.SaveAs(filename); ???????????return Content("OK"); ???????} ???????public ActionResult FileDownLoad() ???????{ ???????????string path = Server.MapPath(@"C:\Users\Administrator\Desktop\自己练习\上传下载\UpLoad\UpLoad\Picture\QQ图片20190228155326.png"); ???????????FileStream fs = new FileStream(path,FileMode.Open); ???????????return File(fs,"text/plain","a.jpg"); ???????}2、将Excal导入datatable（控制台应用）
static void Main(string[] args) ???????{ ???????????Workbook wk = new Workbook(@"C:\Users\admin\Desktop\user.xlsx"); ???????????//获取数据所在的单元格 ???????????Cells cells = wk.Worksheets[0].Cells; ???????????for (int i = 0; i < cells.MaxDataRow; i++) ???????????{ ???????????????for (int j = 0; j < cells.MaxDataColumn; j++) ???????????????{ ???????????????????Console.Write(cells[i,j].Value+"\t"); ???????????????} ???????????} ???????????Console.ReadKey(); ???????}3、提取数据库数据到Excel（控制台应用）
//提取数据到Excal ???????static void Main(string[] args) ???????{ ???????????//读取证书 ???????????License license = new License(); ???????????license.SetLicense(@"C:\Users\admin\Desktop\自己练习\表达式树\从数据库中读取数据到Excal\Aid\License.lic"); ???????????DataTable dt = GetDataTable(); ???????????//全新的工作簿 ???????????Workbook wb = new Workbook(); ???????????//工作表 ???????????Worksheet ws = wb.Worksheets[0]; ???????????ws.Cells.ImportDataTable(dt,true,"A1"); ???????????wb.Save(@"C:\Users\admin\Desktop\\user.xlsx",SaveFormat.Xlsx); ???????????Console.WriteLine("读取成功"); ???????????Console.ReadKey(); ???????} ???????public static DataTable GetDataTable() ???????{ ???????????string sql = "select * from Student"; ???????????return DBHelper.GetDataTable(sql); ???????}4、Word读取（控制台应用）
static void Main(string[] args) ???????{ ???????????using (StreamReader reader = new StreamReader(@"D:\《雪中悍刀行》作者：烽火戏诸侯.txt", Encoding.Default)) ???????????{ ???????????????string line; ???????????????while ((line = reader.ReadLine()) != null) ???????????????{ ???????????????????Console.WriteLine(line); ???????????????} ???????????} ???????????Console.ReadKey(); ???????}5、Word写入（控制台应用）
static void Main(string[] args) ???????{ ???????????if (File.Exists(@"C:\Users\Administrator\Desktop\新建 Microsoft Word 文档")) ???????????{ ???????????????Console.WriteLine("文件已存在"); ???????????} ???????????FileStream fs = new FileStream(@"C:\Users\Administrator\Desktop\新建 Microsoft Word 文档", FileMode.Create); ???????????StreamWriter sw = new StreamWriter(fs); ???????????sw.WriteLine("床前明月光"); ???????????sw.WriteLine("疑是地上霜"); ???????????sw.Close(); ???????????fs.Close(); ???????????Console.WriteLine("写入成功"); ???????????Console.ReadKey(); ???????}文件上传下下载（不包含断点续传） ?Excel，Word导入导出基础
原文地址：https://www.cnblogs.com/dujian123/p/10582695.html