MVC文件上传和下载

1.单个文件上传

HTML写法：form表单中加enctype="multipart/form-data"

 <form aciont="" method="post" enctype="multipart/form-data">
     <input type="file" id="file" name="file" />
     <br/>
     <input type="submit" name="提交"/>
 </form>

HTML写法：

View写法：同样 form表单中加enctype="multipart/form-data"

 @using (Html.BeginForm("Add", null, FormMethod.Post, new { enctype = "multipart/form-data" }))
 {
     <input type="file" id="file" name="file" />
     <br/>
     <input type="submit" value="提交"/>
 }

View写法：

后台Controller中的写法：

 [HttpPost]
 public ActionResult Add(HttpPostedFileBase file)
 {
     string path = "/uploadImg/";
    if (!Directory.Exists(Server.MapPath(path)))
    {
         Directory.CreateDirectory(Server.MapPath(path));
    }
    if (file != null)
    {
        string filePath = string.Format("{0}/{1}{2}", path, System.Guid.NewGuid(), System.IO.Path.GetExtension(file.FileName));
        file.SaveAs(Server.MapPath(filePath));
    }
    return View();
  }

Controller

2.多个文件上传

就是form表单中多个input file

 @using (Html.BeginForm("Index", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
 {
     <input type="file" id="file" name="file1" />
     <input type="file" id="file" name="file2" />
     <input type="file" id="file" name="file3" />
     <input type="file" id="file" name="file4" />
     <input type="file" id="file" name="file5" />
     <input type="file" id="file" name="file6" />
     <br/>
     <input type="submit" value="提交"/>
 }

View

 public class HomeController:Controller
 {
  public ActionResult Index()
   {
     foreach (string upload in Request.Files)
     {
       if (!Request.Files[upload].HasFile()) continue;
       string path = "/uploadImg/";
       string filename = Path.GetFileName(Request.Files[upload].FileName);
       Request.Files[upload].SaveAs(Path.Combine(path, filename));
     }
     return View();
   }
  }

Controller

3.文件下载

HTML中：<a href="/GetFile">下载文件</a>
View中：@Html.ActionLink("下载文件", "Download", "Home");

直接下载到默认下载中

  public class HomeController : Controller
     {
      public FilePathResult GetFileFromDisk()
         {
             string path = @"/uploadImg/";
             string fileName = "5141fb63-955b-4f0b-9f53-ab770329e6f5.png";
             return File(path + fileName, "image/png", fileName);
         }

         public FileStreamResult StreamFileFromDisk()
         {
             string path = AppDomain.CurrentDomain.BaseDirectory + "uploadImg/";
             string fileName = "5141fb63-955b-4f0b-9f53-ab770329e6f5.png";
             return File(new FileStream(path + fileName, FileMode.Open), "image/png", fileName);
         }
     }
 }

Controller