Angularjs $http post file and form data

I had similar problem when had to upload file and send user token info at the same time. transformRequest along with forming FormData helped:

        $http({
            method: 'POST',
            url: '/upload-file',
            headers: {
                'Content-Type': 'multipart/form-data'
            },
            data: {
                email: Utils.getUserInfo().email,
                token: Utils.getUserInfo().token,
                upload: $scope.file
            },
            transformRequest: function (data, headersGetter) {
                var formData = new FormData();
                angular.forEach(data, function (value, key) {
                    formData.append(key, value);
                });

                var headers = headersGetter();
                delete headers['Content-Type'];

                return formData;
            }
        })
        .success(function (data) {

        })
        .error(function (data, status) {

        });

For getting file $scope.file I used custom directive:

app.directive('file', function () {
    return {
        scope: {
            file: '='
        },
        link: function (scope, el, attrs) {
            el.bind('change', function (event) {
                var file = event.target.files[0];
                scope.file = file ? file : undefined;
                scope.$apply();
            });
        }
    };
});

Html:

<input type="file" file="file" required />

I was unable to get Pavel's answer working as in when posting to a Web.Api application.

The issue appears to be with the deleting of the headers.

headersGetter();
delete headers['Content-Type'];

In order to ensure the browsers was allowed to default the Content-Type along with the boundary parameter, I needed to set the Content-Type to undefined. Using Pavel's example the boundary was never being set resulting in a 400 HTTP exception.

The key was to remove the code deleting the headers shown above and to set the headers content type to null manually. Thus allowing the browser to set the properties.

headers: {'Content-Type': undefined}

Here is a full example.

$scope.Submit = form => {
                $http({
                    method: 'POST',
                    url: 'api/FileTest',
                    headers: {'Content-Type': undefined},
                    data: {
                        FullName: $scope.FullName,
                        Email: $scope.Email,
                        File1: $scope.file
                    },
                    transformRequest: function (data, headersGetter) {
                        var formData = new FormData();
                        angular.forEach(data, function (value, key) {
                            formData.append(key, value);
                        });
                        return formData;
                    }
                })
                .success(function (data) {

                })
                .error(function (data, status) {

                });

                return false;
            }

I recently wrote a directive that supports native multiple file uploads. The solution I've created relies on a service to fill the gap you've identified with the $http service. I've also included a directive, which provides an easy API for your angular module to use to post the files and data.

Example usage:

<lvl-file-upload
    auto-upload='false'
    choose-file-button-text='Choose files'
    upload-file-button-text='Upload files'
    upload-url='http://localhost:3000/files'
    max-files='10'
    max-file-size-mb='5'
    get-additional-data='getData(files)'
    on-done='done(files, data)'
    on-progress='progress(percentDone)'
    on-error='error(files, type, msg)'/>

You can find the code on github, and the documentation on my blog

It would be up to you to process the files in your web framework, but the solution I've created provides the angular interface to getting the data to your server. The angular code you need to write is to respond to the upload events

angular
    .module('app', ['lvl.directives.fileupload'])
    .controller('ctl', ['$scope', function($scope) {
        $scope.done = function(files,data} { /*do something when the upload completes*/ };
        $scope.progress = function(percentDone) { /*do something when progress is reported*/ };
        $scope.error = function(file, type, msg) { /*do something if an error occurs*/ };
        $scope.getAdditionalData = function() { /* return additional data to be posted to the server*/ };

    });

Please, have a look on my implementation. You can wrap the following function into a service:

function(file, url) {
  var fd = new FormData();

  fd.append('file', file);

  return $http.post(url, fd, {
    transformRequest: angular.identity,
    headers: { 'Content-Type': undefined }
  });
}

Please notice, that file argument is a Blob. If you have base64 version of a file - it can be easily changed to Blob like so:

fetch(base64).then(function(response) {
  return response.blob(); 
}).then(console.info).catch(console.error);

You can also upload using HTML5. You can use this AJAX uploader.

The JS code is basically:

  $scope.doPhotoUpload = function () {
    // ..
    var myUploader = new uploader(document.getElementById('file_upload_element_id'), options);
    myUploader.send();
    // ..
  }

Which reads from an HTML input element

<input id="file_upload_element_id" type="file" onchange="angular.element(this).scope().doPhotoUpload()">