Angular - pass scope to service and set value - angularjs

Question

I cannot pass/set the value to the text-area outside the controller.
I am uploading an excel and regarding the upload status I want to set some data to a text-area.
This is my code so far:
app.service('fileUpload', ['$http', function ($http) {
this.uploadFileToUrl = function(file, uploadUrl, commentArea){
var fd = new FormData();
fd.append('file', file);
$http.post(uploadUrl, fd, {
transformRequest: angular.identity,
headers: {'Content-Type': undefined}
})
.success(function(){
/* commentArea.append('This is not working');
commentArea = 'This is not working';
$scope.outputImportObject = 'This is not working';
*/
alert('The file was succesfully uploaded!');
})
.error(function(){
alert('There was an error while inserting the file!');
});
}
}]);
app.controller('UploadCtrl', ['$scope', 'fileUpload', function($scope, fileUpload){
$scope.uploadFile = function(){
$scope.outputImportObject = 'This is working';
var file = $scope.myFile;
var commentArea = $scope.outputImportObject;
fileUpload.uploadFileToUrl(file, ws_url+'upload_excel.php',commentArea);
};
}]);

Answer 1

This typically seems a case where you should be using promises.
From your services you should return a promise and based on their resolution or rejection, you should bind the variable on controller.
your service should look something like:
app.service('fileUpload', ['$http', function ($http) {
this.uploadFileToUrl = function(file, uploadUrl, commentArea){
var fd = new FormData();
fd.append('file', file);
return
$http.post(uploadUrl, fd, {
transformRequest: angular.identity,
headers: {'Content-Type': undefined}
})
}
}]);
Since, http itself return a promise, you can directly return it, instead of making your custom promise.
and your controller should be like:
app.controller('UploadCtrl', ['$scope', 'fileUpload', function($scope, fileUpload){
$scope.uploadFile = function(){
$scope.outputImportObject = 'This is working';
var file = $scope.myFile;
var commentArea = $scope.outputImportObject;
fileUpload.uploadFileToUrl(file, ws_url+'upload_excel.php',commentArea)
.then(doThisOnSuccess, doThisOnFailure);
function doThisOnSuccess(){
code for binding to text area should go here
}
function doThisOnFailure(){
}
};
}]);