AngularJS Upload Multiple Files with FormData API

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How to POST FormData Using the $http Service

When using the FormData API to POST files and data, it is important to set the Content-Type header to undefined.

var fd = new FormData()
for (var i in $scope.files) {
    fd.append("fileToUpload", $scope.files[i]);
}
var config = {headers: {'Content-Type': undefined}};

var httpPromise = $http.post(url, fd, config);

By default the AngularJS framework uses content type application/json. By setting Content-Type: undefined, the AngularJS framework omits the content type header allowing the XHR API to set the content type. When sending a FormData object, the XHR API sets the content type to multipart/form-data with the proper boundaries and base64 encoding.

For more information, see MDN Web API Reference – XHR Send method

How did you get the file information into $scope.files?

How to enable <input type="file"> to work with ng-model

This directive also enables <input type="file"> to automatically work with the ng-change and ng-form directives.

angular.module("app",[]);

angular.module("app").directive("selectFilesNg", function() {
  return {
    require: "ngModel",
    link: function postLink(scope,elem,attrs,ngModel) {
      elem.on("change", function(e) {
        var files = elem[0].files;
        ngModel.$setViewValue(files);
      })
    }
  }
});
<script src="https://unpkg.com/angular/angular.js"></script>
  <body ng-app="app">
    <h1>AngularJS Input `type=file` Demo</h1>
    
    <input type="file" select-files-ng ng-model="fileArray" multiple>

    <code><table ng-show="fileArray.length">
    <tr><td>Name</td><td>Date</td><td>Size</td><td>Type</td><tr>
    <tr ng-repeat="file in fileArray">
      <td>{{file.name}}</td>
      <td>{{file.lastModified | date  : 'MMMdd,yyyy'}}</td>
      <td>{{file.size}}</td>
      <td>{{file.type}}</td>
    </tr>
    </table></code>
    
  </body>

RECOMMENDED: POST Binary Files Directly

Posting binary files with multi-part/form-data is inefficient as the base64 encoding adds an extra 33% overhead. If the server API accepts POSTs with binary data, post the file directly.

See How to POST binary files with AngularJS (with DEMO)

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