如何使用 jQuery 在 ASP.NET MVC 中上传文件?

How to upload file in ASP.NET MVC with jQuery?

我需要在 ASP.NET MVC 中上传文件。纯 javascript 代码有效(见下文),但如果我将发送部分转换为 jQuery,它会给我一个 jquery 错误(第 8458 行)。

错误:

0x8000fff - JavaScript runtime error: Argument not optional
code: 
8453 jQuery.param = function( a, traditional ) {
8454    var prefix,
8455        s = [],
8456        add = function( key, value ) {
8457            // If value is a function, invoke it and return its value
8458            value = jQuery.isFunction( value ) ? value() : ( value == null ? "" : value );
8459            s[ s.length ] = encodeURIComponent( key ) + "=" + encodeURIComponent( value );
8460        };

html:

<form data-bind='submit: upload'>
  <input type='file' id='fileInput' />
  <input type='submit' value='upload' />
</form>

js:

that.upload = function(){
  var data = new FormData();
  var fileInput = $('#fileInput')[0];
  var file = fileInput.files[0];
  data.append(file.name, file);
  var url = 'blah/Upload?id=' + that.id();

  // this pure js works
  var xhr = new XMLHttpRequest();
  xhr.open('post', url);
  xhr.send(data);

  // this jquery code does NOT work
  $.ajax({
      type: 'post',
      dataType: json',
      url: url,
      data: data,
  });
};

控制器:

public JsonResult Upload(string id){
  return Json(JsonConvert.SerializeObject(true), JsonRequestBehavior.DenyGet);
}

您需要添加 2 个额外的 ajax 选项,processData: falsecontentType: false

$.ajax({
  type: 'post',
  dataType: json',
  url: url,
  data: data,
  processData: false, // add
  contentType: false, // add
  ....
});

旁注:您应该使用 Url.Action() 以确保正确生成 url

var url = '@Url.Action("Upload", "blah")',

并将 id 值添加到 FormData

data.append(id, that.id);