FormData密钥不通过

Question

I use external class for making object variable into FormData variable. All of the keys go through, all but One for File object.

Here is that external class: https://github.com/therealparmesh/object-to-formdata

This is how I create objects and make them into FormData

var _documents = [];

for (var i = 0; i < arrayOfFiles.length; i++) {

  var document = {
     File: arrayOfFiles[i].file.nativeFile,
     DocumentId: arrayOfFiles[i].documentId,
     DocumentType: arrayOfFiles[i].documentName
  };

  _documents.push(document);
}

var uploadedInformation = {
       LoanID: 1452465,
       documents: _documents
};

var options = {
   indices: true,
   nulls: true
};

var a = objectToFormData(uploadedInformation, options);

for (var pair of a.entries()) {
     console.log(pair[0] + ', ' + pair[1]);
}

jQuery.ajaxSettings.traditional = true;
$.ajax({
    async: false,
    cache: false,
    contentType: false,
    processData: false,
    type: 'POST',
    url:  '@Url.Action("UploadFile", "Home")',
    data: a
});

Code for controller:

[HttpPost]
        [ActionName("UploadFile")]
        public ActionResult UploadFile(UploadedInformation uploadedInformation)
        {
            _ = Request.Form;
            return View();
        }

UploadedFile class:

public class UploadedInformation
    {

        public long LoanID { get; set; }
        public IEnumerable<Document> Documents { get; set; }

    }

Document class:

public class Document
{

      public HttpPostedFileBase File { get; set;}
      public string DocumentId { get; set;}
      public string DocumentType { get; set; }
}

All of the items bind perfectly, except for File . In browser debugger keys and values are:

LoanID, 1452465
documents[0][File], [object File]
documents[0][DocumentId], 1
documents[0][DocumentType], Passport

_=Request.Form also displays only 3 keys without documents[0][File]

Update: I changed controller to

public ActionResult UploadFile(IEnumerable<HttpPostedFileBase> file, IEnumerable<string> documentType, IEnumerable<string>documentId, long loanId){...}

and _=Request.Form still shows nothing with file , however file list is populated

Another update: Apparently, this time file items shows only in _=Request.File

Answer 1

Due to the way that the controller is handling the file upload parts of the request, I suspect you may need to make some adjustments to your process and allow for the fact that the files are being separated from the main object.

I've included some adjustments to your code below (note, this is untested so you may need to experiment a little), assuming that the files come through in the same order as you Documents, then just run a match up process before running your own process.

Code for controller:

[HttpPost]
        [ActionName("UploadFile")]
        public ActionResult UploadFile(List<HttpPostedFileBase> myFiles, UploadedInformation uploadedInformation)
        {
            for (var i = 0; i <uploadedInformation.Documents.Length; i++)
            {
                uploadedInformation.Documents[i].File = myFiles[i];
            }

            // Do stuff

            return View();
        }

In the event that the order of the files cannot be assumed, you can add the filename to the data to aid with matching on the server side

Javascript

var _documents = [];

for (var i = 0; i < arrayOfFiles.length; i++) {

  var document = {
     File: arrayOfFiles[i].file.nativeFile,
     FileName: arrayOfFiles[i].file.name,
     DocumentId: arrayOfFiles[i].documentId,
     DocumentType: arrayOfFiles[i].documentName
  };

  _documents.push(document);
}