（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
我必须上传100kb的文件块，最后一个上传文件使用命令存储在数据库中。我希望，这会对你有所帮助。
public HttpResponseMessage Post(AttachmentUploadForm form)
{
var response = new WebApiResultResponse
{
IsSuccess = true,
RedirectRequired = false
};
var tempFilesFolder = Sanelib.Common.SystemSettings.Globals.CreateOrGetCustomPath("Temp\\" + form.FileId);
File.WriteAllText(tempFilesFolder + "\\" + form.ChunkNumber + ".temp", form.ChunkData);
if (form.ChunkNumber < Math.Ceiling((double)form.Size / 102400)) return Content(response);
var folderInfo = new DirectoryInfo(tempFilesFolder);
var totalFiles = folderInfo.GetFiles().Length;
var sb = new StringBuilder();
for (var i = 1; i <= totalFiles; i++)
{
sb.Append(File.ReadAllText(tempFilesFolder + "\\" + i + ".temp"));
}
var base64 = sb.ToString();
base64 = base64.Substring(base64.IndexOf(',') + 1);
var fileBytes = Convert.FromBase64String(base64);
var fileStream = new FileStream(tempFilesFolder + "\\" + form.Name, FileMode.OpenOrCreate, FileAccess.ReadWrite);
fileStream.Seek(fileStream.Length, SeekOrigin.Begin);
fileStream.Write(fileBytes, 0, fileBytes.Length);
fileStream.Close();
Directory.Delete(tempFilesFolder, true);
var md5 = MD5.Create();
var command = Mapper.Map<AttachmentUploadForm, AddAttachment>(form);
command.FileData = fileBytes;
command.FileHashCode = BitConverter.ToString(md5.ComputeHash(fileBytes)).Replace("-", "");
return ExecuteCommand(command);
}
Javascript（Knockout Js）
define(['util', 'ajax'], function (util, ajax) {
"use strict";
var exports = {},
ViewModel, Attachment, FileObject;
//File Upload
FileObject = function (file, parent) {
var self = this;
self.fileId = util.guid();
self.name = ko.observable(file.name);
self.type = ko.observable(file.type);
self.size = ko.observable();
self.fileData = null;
self.fileSize = ko.observable(file.size / 1024 / 1024);
self.chunks = 0;
self.currentChunk = ko.observable();
var reader = new FileReader();
// Closure to capture the file information.
reader.onload = (function (e) {
self.fileData = e.target.result;
self.size(self.fileData.length);
self.chunks = Math.ceil(self.size() / 102400);
self.sendChunk(1);
});
reader.readAsDataURL(file);
self.percentComplete = ko.computed(function () {
return self.currentChunk() * 100 / self.chunks;
}, self);
self.cancel = function (record) {
parent.uploads.remove(record);
};
self.sendChunk = function (number) {
var start = (number - 1) * 102400;
var end = number * 102400;
self.currentChunk(number);
var form = {
fileId: self.fileId,
name: self.name(),
fileType: self.type(),
Size: self.size(),
FileSize: self.fileSize(),
chunkNumber: number,
chunkData: self.fileData.slice(start, end),
entityTypeValue: parent.entityTypeValue,
ReferenceId: parent.detail.id,
ReferenceName: parent.detail.name
};
ajax.post('Attachment', JSON.stringify(form)).done(function (response) {
if (number < self.chunks)
self.sendChunk(number + 1);
if (response.id != null) {
parent.attachments.push(new Attachment(response));
self.cancel(response);
}
});
};
};
Attachment = function (data) {
var self = this;
self.id = ko.observable(data.id);
self.name = ko.observable(data.name);
self.fileType = ko.observable(data.fileType);
self.fileSize = ko.observable(data.fileSize);
self.fileData = ko.observable(data.fileData);
self.typeName = ko.observable(data.typeName);
self.description = ko.observable(data.description).revertable();
self.tags = ko.observable(data.tags).revertable();
self.operationTime = ko.observable(moment(data.createdOn).format('MM-DD-YYYY HH:mm:ss'));
self.description.subscribe(function () {
var form = {
Id: self.id(),
Description: self.description(),
Tags: self.tags()
};
ajax.put('attachment', JSON.stringify(form)).done(function (response) {
self.description.commit();
return;
}).fail(function () {
self.description.revert();
});
});
self.tags.subscribe(function () {
var form = {
Id: self.id(),
Description: self.description(),
Tags: self.tags()
};
ajax.put('attachment', JSON.stringify(form)).done(function (response) {
self.tags.commit();
return;
}).fail(function () {
self.tags.revert();
});
});
};
ViewModel = function (data) {
var self = this;
// for attachment
self.attachments = ko.observableArray([]);
$.each(data.attachments, function (row, val) {
self.attachments.push(new Attachment(val));
});
self.deleteAttachmentRecord = function (record) {
if (!confirm("Are you sure you want to delete this record?")) return;
ajax.del('attachment', record.id(), { async: false }).done(function () {
self.attachments.remove(record);
return;
});
};
exports.exec = function (model) {
console.log(model);
var viewModel = new ViewModel(model);
ko.applyBindings(viewModel, document.getElementById('ShowAuditDiv'));
};
return exports;
});
HTML代码：
<div class="row-fluid spacer-bottom fileDragHolder">
<div class="spacer-bottom"></div>
<div class="legend">
Attachments<div class="pull-right">@Html.AttachmentPicker("AC")</div>
</div>
<div>
<div class="row-fluid spacer-bottom">
<div style="overflow: auto">
<table class="table table-bordered table-hover table-condensed" data-bind="visible: uploads().length > 0 || attachments().length > 0">
<thead>
<tr>
<th class=" btn btn-primary col-md-2" style="text-align: center">
Name
</th>
<th class="btn btn-primary col-md-1" style="text-align: center">Type</th>
<th class="btn btn-primary col-md-1" style="text-align: center">Size (MB)</th>
<th class="btn btn-primary col-md-1" style="text-align: center">Upload Time</th>
<th class="btn btn-primary col-md-1" style="text-align: center">Tags</th>
<th class="btn btn-primary col-md-6" style="text-align: center">Description</th>
<th class="btn btn-primary col-md-1" style="text-align: center">Delete</th>
</tr>
</thead>
<tbody>
<!-- ko foreach: attachments -->
<tr>
<td style="text-align: center" class="col-xs-2"><a href="#" data-bind="text: name,attr:{'href':'/attachment/index?id=' + id()}"></a></td>
<td style="text-align: center" class="col-xs-1"><span data-bind="text: fileType"></span></td>
<td style="text-align: center" class="col-xs-1"><span data-bind="text: fileSize"></span></td>
<td style="text-align: center" class="col-xs-2"><span data-bind="text: operationTime"></span></td>
<td style="text-align: center" class="col-xs-3"><div contenteditable="true" data-bind="editableText: tags"></div></td>
<td style="text-align: center" class="col-xs-4"><div contenteditable="true" data-bind="editableText: description"></div></td>
<td style="text-align: center" class="col-xs-1"><button class="btn btn-primary" data-bind="click:$root.deleteAttachmentRecord"><i class="icon-trash"></i></button></td>
</tr>
<!-- /ko -->
</tbody>
<tfoot data-bind="visible: uploads().length > 0">
<tr>
<th colspan="6">Files upload status</th>
</tr>
<tr>
<th>Name</th>
<th>Type</th>
<th>Size (MB)</th>
<th colspan="2">Status</th>
<th></th>
</tr>
<!-- ko foreach: uploads -->
<tr>
<td><span data-bind="text: name"></span></td>
<td><span data-bind="text: type"></span></td>
<td><span data-bind="text: fileSize"></span></td>
<td colspan="2">
<div class="progress">
<div class="progress-bar" data-bind="style: { width: percentComplete() + '%' }"></div>
</div>
</td>
<td style="text-align: center"><button class="btn btn-primary" data-bind="click:cancel"><i class="icon-trash"></i></button></td>
</tr>
<!-- /ko -->
</tfoot>
</table>
</div>
<div data-bind="visible: attachments().length == 0" class="span12" style="margin-left:0">
<span>No Records found.</span>
</div>
</div>
其他回答
我在做文件上传概念时也遇到过同样的错误。我知道开发人员为这个问题提供了很多答案。
尽管我回答这个问题的原因是，由于下面提到的疏忽错误，我犯了这个错误。
<input type="file" name="uploadedFile" />
在指定name属性时，请确保控制器参数也具有相同的名称值“uploadedFile”。这样地：
[HttpPost]
public ActionResult FileUpload(HttpPostedFileBase uploadedFile)
{
}
否则它不会被映射。
我给你简单易懂的方法。
首先，必须在.Cshtml文件中编写以下代码。
<input name="Image" type="file" class="form-control" id="resume" />
然后在控制器中输入以下代码：
if (i > 0) {
HttpPostedFileBase file = Request.Files["Image"];
if (file != null && file.ContentLength > 0) {
if (!string.IsNullOrEmpty(file.FileName)) {
string extension = Path.GetExtension(file.FileName);
switch ((extension.ToLower())) {
case ".doc":
break;
case ".docx":
break;
case ".pdf":
break;
default:
ViewBag.result = "Please attach file with extension .doc , .docx , .pdf";
return View();
}
if (!Directory.Exists(Server.MapPath("~") + "\\Resume\\")) {
System.IO.Directory.CreateDirectory(Server.MapPath("~") + "\\Resume\\");
}
string documentpath = Server.MapPath("~") + "\\Resume\\" + i + "_" + file.FileName;
file.SaveAs(documentpath);
string filename = i + "_" + file.FileName;
result = _objbalResume.UpdateResume(filename, i);
Attachment at = new Attachment(documentpath);
//ViewBag.result = (ans == true ? "Thanks for contacting us.We will reply as soon as possible" : "There is some problem. Please try again later.");
}
} else {
...
}
}
为此，您必须根据您的数据库制作BAL和DAL层。
如果你碰巧像我一样在这里跌跌撞撞，想知道尽管代码正确，为什么你的代码仍然不工作。然后，请在输入控件中查找name属性，您可能会意外错过或从未将其放在首位。
<input class="custom-file-input" name="UploadFile" id="UploadFile" type="file" onchange="ValidateFile(this);" accept=".xls, .xlsx">
下面是我的工作示例：
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<ActionResult> Create(Product product, HttpPostedFileBase file)
{
if (!ModelState.IsValid)
return PartialView("Create", product);
if (file != null)
{
var fileName = Path.GetFileName(file.FileName);
var guid = Guid.NewGuid().ToString();
var path = Path.Combine(Server.MapPath("~/Content/Uploads/ProductImages"), guid + fileName);
file.SaveAs(path);
string fl = path.Substring(path.LastIndexOf("\\"));
string[] split = fl.Split('\\');
string newpath = split[1];
string imagepath = "Content/Uploads/ProductImages/" + newpath;
using (MemoryStream ms = new MemoryStream())
{
file.InputStream.CopyTo(ms);
byte[] array = ms.GetBuffer();
}
var nId = Guid.NewGuid().ToString();
// Save record to database
product.Id = nId;
product.State = 1;
product.ImagePath = imagepath;
product.CreatedAt = DateTime.Now;
db.Products.Add(product);
await db.SaveChangesAsync();
TempData["message"] = "ProductCreated";
//return RedirectToAction("Index", product);
}
// after successfully uploading redirect the user
return Json(new { success = true });
}
提供完整的解决方案
首先在MVC视图中使用.CShtml中的输入
<input type="file" id="UploadImg" /></br>
<img id="imgPreview" height="200" width="200" />
现在调用Ajax调用
$("#UploadImg").change(function () {
var data = new FormData();
var files = $("#UploadImg").get(0).files;
if (files.length > 0) {
data.append("MyImages", files[0]);
}
$.ajax({
// url: "Controller/ActionMethod"
url: "/SignUp/UploadFile",
type: "POST",
processData: false,
contentType: false,
data: data,
success: function (response)
{
//code after success
$("#UploadPhoto").val(response);
$("#imgPreview").attr('src', '/Upload/' + response);
},
error: function (er) {
//alert(er);
}
});
});
控制器Json呼叫
[HttpGet]
public JsonResult UploadFile()
{
string _imgname = string.Empty;
if (System.Web.HttpContext.Current.Request.Files.AllKeys.Any())
{
var pic = System.Web.HttpContext.Current.Request.Files["MyImages"];
if (pic.ContentLength > 0)
{
var fileName = Path.GetFileName(pic.FileName);
var _ext = Path.GetExtension(pic.FileName);
_imgname = Guid.NewGuid().ToString();
var _comPath = Server.MapPath("/MyFolder") + _imgname + _ext;
_imgname = "img_" + _imgname + _ext;
ViewBag.Msg = _comPath;
var path = _comPath;
tblAssignment assign = new tblAssignment();
assign.Uploaded_Path = "/MyFolder" + _imgname + _ext;
// Saving Image in Original Mode
pic.SaveAs(path);
}
}
return Json(Convert.ToString(_imgname), JsonRequestBehavior.AllowGet);
}
