(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
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。
其他回答
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);
}
}
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();
}
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);
}
Html:
@using (Html.BeginForm("StoreMyCompany", "MyCompany", FormMethod.Post, new { id = "formMyCompany", enctype = "multipart/form-data" }))
{
<div class="form-group">
@Html.LabelFor(model => model.modelMyCompany.Logo, htmlAttributes: new { @class = "control-label col-md-3" })
<div class="col-md-6">
<input type="file" name="Logo" id="fileUpload" accept=".png,.jpg,.jpeg,.gif,.tif" />
</div>
</div>
<br />
<div class="form-group">
<div class="col-md-offset-3 col-md-6">
<input type="submit" value="Save" class="btn btn-success" />
</div>
</div>
}
背后代码:
public ActionResult StoreMyCompany([Bind(Exclude = "Logo")]MyCompanyVM model)
{
try
{
byte[] imageData = null;
if (Request.Files.Count > 0)
{
HttpPostedFileBase objFiles = Request.Files["Logo"];
using (var binaryReader = new BinaryReader(objFiles.InputStream))
{
imageData = binaryReader.ReadBytes(objFiles.ContentLength);
}
}
if (imageData != null && imageData.Length > 0)
{
//Your code
}
dbo.SaveChanges();
return RedirectToAction("MyCompany", "Home");
}
catch (Exception ex)
{
Utility.LogError(ex);
}
return View();
}
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。