asp.net-mvcvue.jsaxiosform-dataformcollection

File Uploaded from Vue.JS UI not being captured by MVC Controller


So in my Vue component, I have the following file upload dialog.

<div class="file has-name is-right">
  <label class="file-label">
    <input class="file-input" type="file" v-on:change="HandleFileUpload" accept=".pdf">
    <span class="file-cta">
      <span class="file-icon">
        <i class="icon-file-pdf"></i>
      </span>
      <span class="file-label">
        Choose a file…
      </span>
    </span>
    <span class="file-name" v-text="UploadFileName" style="width: 16em" />
  </label>
</div>

Which is handled by the following method in my methods section:

HandleFileUpload(e) {
  var files = e.target.files || e.dataTransfer.files;
  console.warn(files);
  if(files.length > 0) {
    var uploadFile = files[0];
    this.UploadFileName = uploadFile.name;
    var formData = new FormData();
    formData.append('Foo', this.Foo);
    formData.append('File', uploadFile, this.UploadFileName);
    axios.post(
      '/Foo/Upload',
      data,
      { headers: { 'Content-Type': 'multipart/form-data' } }
    ).then(/* logic to handle callback */);
  } else {
    this.UploadFileName = null;
  }
}

And finally my MVC controller, wherein lies the issue

[HttpPost]
public ActionResult Upload(FormCollection data)
{
  var Foo= data.Get("Foo").Trim();
  var Files = data.Get("File");
  /* Rest of the method */
}

Files in the MVC controller is null, despite being populated with the actual file data in the JS and in the network call when I inspect it with the developer tools. Am I missing something from the FormData interactions with FormCollection?


Solution

  • Hm, try this approach, I just checked a web app I created that uses ASP.NET and axios for posting and my JS looks pretty much identical to yours, in ASP.NET, I am basically doing this:

    HttpContext context = System.Web.HttpContext.Current;
    HttpPostedFile postedFile = context.Request.Files.Count > 0
                    ? context.Request.Files.Get(0)
                    : null;