(前言:这个问题是关于2011年发布的ASP.NET MVC 3.0,而不是关于2019年发布的ASP.NETCore 3.0)
我想用asp.net mvc上传文件。如何使用html输入文件控件上载文件?
(前言:这个问题是关于2011年发布的ASP.NET MVC 3.0,而不是关于2019年发布的ASP.NETCore 3.0)
我想用asp.net mvc上传文件。如何使用html输入文件控件上载文件?
当前回答
使用formdata上载文件
.cshtml文件
var files = $("#file").get(0).files;
if (files.length > 0) {
data.append("filekey", files[0]);}
$.ajax({
url: '@Url.Action("ActionName", "ControllerName")', type: "POST", processData: false,
data: data, dataType: 'json',
contentType: false,
success: function (data) {
var response=data.JsonData;
},
error: function (er) { }
});
服务器端代码
if (System.Web.HttpContext.Current.Request.Files.AllKeys.Any())
{
var pic = System.Web.HttpContext.Current.Request.Files["filekey"];
HttpPostedFileBase filebase = new HttpPostedFileWrapper(pic);
var fileName = Path.GetFileName(filebase.FileName);
string fileExtension = System.IO.Path.GetExtension(fileName);
if (fileExtension == ".xls" || fileExtension == ".xlsx")
{
string FileName = Guid.NewGuid().GetHashCode().ToString("x");
string dirLocation = Server.MapPath("~/Content/PacketExcel/");
if (!Directory.Exists(dirLocation))
{
Directory.CreateDirectory(dirLocation);
}
string fileLocation = Server.MapPath("~/Content/PacketExcel/") + FileName + fileExtension;
filebase.SaveAs(fileLocation);
}
}
其他回答
在视图中:
<form action="Categories/Upload" enctype="multipart/form-data" method="post">
<input type="file" name="Image">
<input type="submit" value="Save">
</form>
而控制器中的以下代码:
public ActionResult Upload()
{
foreach (string file in Request.Files)
{
var hpf = this.Request.Files[file];
if (hpf.ContentLength == 0)
{
continue;
}
string savedFileName = Path.Combine(
AppDomain.CurrentDomain.BaseDirectory, "PutYourUploadDirectoryHere");
savedFileName = Path.Combine(savedFileName, Path.GetFileName(hpf.FileName));
hpf.SaveAs(savedFileName);
}
...
}
public ActionResult FileUpload(upload mRegister) {
//Check server side validation using data annotation
if (ModelState.IsValid) {
//TO:DO
var fileName = Path.GetFileName(mRegister.file.FileName);
var path = Path.Combine(Server.MapPath("~/Content/Upload"), fileName);
mRegister.file.SaveAs(path);
ViewBag.Message = "File has been uploaded successfully";
ModelState.Clear();
}
return View();
}
在控制器中
if (MyModal.ImageFile != null)
{
MyModal.ImageURL = string.Format("{0}.{1}", Guid.NewGuid().ToString(), MyModal.ImageFile.FileName.Split('.').LastOrDefault());
if (MyModal.ImageFile != null)
{
var path = Path.Combine(Server.MapPath("~/Content/uploads/"), MyModal.ImageURL);
MyModal.ImageFile.SaveAs(path);
}
}
在视图中
<input type="hidden" value="" name="..."><input id="ImageFile" type="file" name="ImageFile" src="@Model.ImageURL">
在模态类中
public HttpPostedFileBase ImageFile { get; set; }
在项目的Content文件夹中创建上载文件夹
保存多个文件的简单方法
cshtml
@using (Html.BeginForm("Index","Home",FormMethod.Post,new { enctype = "multipart/form-data" }))
{
<label for="file">Upload Files:</label>
<input type="file" multiple name="files" id="files" /><br><br>
<input type="submit" value="Upload Files" />
<br><br>
@ViewBag.Message
}
控制器
[HttpPost]
public ActionResult Index(HttpPostedFileBase[] files)
{
foreach (HttpPostedFileBase file in files)
{
if (file != null && file.ContentLength > 0)
try
{
string path = Path.Combine(Server.MapPath("~/Files"), Path.GetFileName(file.FileName));
file.SaveAs(path);
ViewBag.Message = "File uploaded successfully";
}
catch (Exception ex)
{
ViewBag.Message = "ERROR:" + ex.Message.ToString();
}
else
{
ViewBag.Message = "You have not specified a file.";
}
}
return View();
}
通常,您还希望传递一个视图模型,而不仅仅是一个文件。在下面的代码中,您将发现一些其他有用的功能:
检查文件是否已附加检查文件大小是否为0检查文件大小是否大于4 MB检查文件大小是否小于100字节检查文件扩展名
可以通过以下代码完成:
[HttpPost]
public ActionResult Index(MyViewModel viewModel)
{
// if file's content length is zero or no files submitted
if (Request.Files.Count != 1 || Request.Files[0].ContentLength == 0)
{
ModelState.AddModelError("uploadError", "File's length is zero, or no files found");
return View(viewModel);
}
// check the file size (max 4 Mb)
if (Request.Files[0].ContentLength > 1024 * 1024 * 4)
{
ModelState.AddModelError("uploadError", "File size can't exceed 4 MB");
return View(viewModel);
}
// check the file size (min 100 bytes)
if (Request.Files[0].ContentLength < 100)
{
ModelState.AddModelError("uploadError", "File size is too small");
return View(viewModel);
}
// check file extension
string extension = Path.GetExtension(Request.Files[0].FileName).ToLower();
if (extension != ".pdf" && extension != ".doc" && extension != ".docx" && extension != ".rtf" && extension != ".txt")
{
ModelState.AddModelError("uploadError", "Supported file extensions: pdf, doc, docx, rtf, txt");
return View(viewModel);
}
// extract only the filename
var fileName = Path.GetFileName(Request.Files[0].FileName);
// store the file inside ~/App_Data/uploads folder
var path = Path.Combine(Server.MapPath("~/App_Data/uploads"), fileName);
try
{
if (System.IO.File.Exists(path))
System.IO.File.Delete(path);
Request.Files[0].SaveAs(path);
}
catch (Exception)
{
ModelState.AddModelError("uploadError", "Can't save file to disk");
}
if(ModelState.IsValid)
{
// put your logic here
return View("Success");
}
return View(viewModel);
}
确保你有
@Html.ValidationMessage("uploadError")
在您的视图中查看验证错误。
还要记住,默认最大请求长度为4MB(maxRequestLength=4096),要上载更大的文件,必须在web.config中更改此参数:
<system.web>
<httpRuntime maxRequestLength="40960" executionTimeout="1100" />
(此处40960=40 MB)。
执行超时是秒的整数。您可能希望将其更改为允许上传大量文件。