IEnumerable array is always null...WebAPI - c#

I'm building a comma separated string and passing it to my WebAPI method like so:
var projectids="";
for (var i = 0; i < chk.length; i++) {
projectids += chk[i].VMIProjectId + ",";
}
//projectids = "1,2,3"
$.ajax({
type: 'POST',
url: "http://localhost:52555/device/6/AddProjectsToDevice",
contentType: 'application/json; charset=utf-8',
dataType: 'json',
data: JSON.stringify(projectids),
success: function (msg) {
},
error: function (data) {
debugger;
}
});
I 'm reaching the WebApi method successfully, but my IEnumerable array projectIds is always null. Here's the method:
[HttpPost]
[Route("device/{deviceId}/AddProjectsToDevice")]
public IEnumerable<VMI_DeviceLinkedProject> AddProjectsToDevice([FromUri]long deviceId,[FromBody] IEnumerable<long> projectIds){}
How do i pass my comma separated list of ids to my WebAPI method? Thanks for reading

Right now your controller action is getting a comma separated string of numbers and not a JSON array ("[1,2,3,4]"), which is why the model binder isn't working:
var projectids = [];
for (var i = 0; i < chk.length; i++) {
projectids.push(chk[i].VMIProjectId);
}
And then the stringified array should bind to the IEnumerable<long> properly.

Instead of passing it as a csv value you can pass it as an array using the same code as below,
var projectIdList =[];
for (var i = 0; i < chk.length; i++) {
projectIdList.push(chk[i].VMIProjectId);
}
Similarly change the parameter name in api method also as projectIdList and pass it.

Related

C# - Jquery : Pass regular params and list<KeyPairValue<string, string>> with $.post from view to controller

I try to pass 'regular' parameters type from an ajax call ($.post) from a view to a controller which is supposed to receive those parameters plus a List>.
I need this List cause those parameters will be different from model.types, and the method in the controller dispatch all params in a switch case to private methods.
I tried several jquery objects builds, JSON.stringify, the array with indexes in the string (I know I can't name columns explicitly... part of my question) which always ends in the List> to null in the backend method.
The 'params' are visible in xhr debug, but the parameter _options is always null (ref controller method).
Here is my vars and my ajax call :
function initDocumentsPreviewsActions() {
$('.documents-list-preview-action').on('click', function () {
if (xhrPreviewLoad != undefined)
xhrPreviewLoad.abort();
$('#documents-preview').html('<div class="general-form-message-loader"></div>');
documentCurrentIndex = $(this).data('btnindex');
setDatatableRowActive();
var documentType = $(this).data('documenttype');
var adherentRessourceId = $(this).data('adherentressourceid');
var annee = $(this).data('annee');
var echeancier = $(this).data('echeancier');
var destinataireid = $(this).data('destinataireid');
var destinatairetypeid = $(this).data('destinatairetypeid');
var emetteurid = $(this).data('emetteurid');
var emetteurmandatid = $(this).data('emetteurmandatid');
var trimestres = $(this).data('trimestres');
var params = [
{ '_annee': '' + annee + '', '_echeancier': '' + echeancier + '', '_trimestres': '' + trimestres + '' }
];
xhrPreviewLoad = $.ajax({
url: '/Documents/PreviewDocumentSingle',
data: {
_documentType: documentType,
_adherentRessourceId: adherentRessourceId,
_annee: annee,
_destinataireId: destinataireid,
_destinataireType: destinatairetypeid,
_emetteurId: emetteurid,
_emetteurMandatId: emetteurmandatid,
_echeancier: echeancier,
_options: JSON.stringify(params)
},
dataType: 'json',
type: 'POST'
}).done(function (documentPartialView) {
$('#documents-preview').html('<img src="' + documentPartialView.src + '"/>');
xhrPreviewLoad = undefined;
});
});
}
xhd Parameters in Firefox debugger :
_documentType AppelCotisation
_adherentRessourceId 836
_annee 2018
_destinataireId 11
_destinataireType Syndicat
_emetteurId 16289
_emetteurMandatId 5986
_echeancier False
_options [{"_annee":"2018","_echeancier":"False","_trimestres":"undefined"}]
Controller method :
[HttpPost]
public JsonResult PreviewDocumentSingle(string _documentType, int _adherentRessourceId, int _destinataireId, string _destinataireType, int _emetteurId, int _emetteurMandatId, List<KeyValuePair<string, string>> _options)
{
//(_options = null)
//some code
return JsonResult
}
I already have done this a long time ago but I cannot put a hand or my brain on it. I'm sure it's a little thing.
I expect to get ALL my parameters correctly or being suggested to declare another List of a different type in the backend (and how to formalize it in front), or Array... well... any help is good to come.
But I'd really like to keep mus ctor in the backend as it is.
I finally findout myself how to solve this simple problem by changing to a Dictionnaray instead of a List> in my controller's method parameters and build a simple js object like this :
var options = {};
options['_annee'] = annee;
options['_echeancier'] = echeancier;
options['_trimestres'] = trimestres;

Ajax call is passing controller name and method name instead of data

I am running into some trouble with my ajax call. Here is the controller code:
[Route("RatingInfo/HandleRequest")]
[HttpPost]
public ActionResult HandleRequest(Dictionary<string, string> textBoxValues)
{
var result = CreateJson(textBoxValues); // This is a simplified example
return Json(result);
}
And here is my Jquery/ajax (Razor syntax):
function PassData () {
var data = {};
$('.divCell input').each(function (index, item) {
var id = $(item).attr('id');
var value = item.value;
data['dictionary[' + index + '].Key'] = id;
data['dictionary[' + index + '].Value'] = value;
});
$.ajax({
url: '#Url.Action("HandleRequest")',
type: 'POST',
dataType: 'JSON',
traditional: true,
data: data,
sucesss: function (result) {
alert('Success');
}
})
}
The idea here is to get the data from each textbox and pass it back to the server as a Dictionary with the id as the key and value as, well, the value.
Stepping through the Chrome debugger, the JS data object is built successfully.
From the debugger:
Local
data: Object
dictionary[0].Key: "Address"
dictionary[0].Value: "123 Main St"
dictionary[1].Key: "ZipCode"
dictionary[1].Value: "99999"
dictionary[2].Key: "Phone1"
dictionary[2].Value: "(555) 555-5555"
...
__proto__: Object
However, when the data is passed back to the controller, the values inside textBoxValues does not contain the passed data. Rather, it contains two key/value pairs with keys controller and action and values the names of the controller and action.
From the Visual Studio debugger:
textBoxValues = Count = 2
[0] = {[controller, RatingInfo]}
[1] = {[action, HandleRequest]}
How can I get Jquery to pass the data rather than the controller/action names? I am confused as to how this can even happen in the first place. Any help would be appreciated.
UPDATE
Sorry, I had put wrong code in.
The reason why this was not working is because the name of the parameter was incorrect, giving you a mismatch.
The below will work for you. Notice the name of dictionary is changed to your parameter textBoxValues:
function PassData() {
var data = {};
$('.divCell input').each(function (index, item) {
var id = $(item).attr('id');
var value = item.value;
data['textBoxValues[' + index + '].Key'] = id;
data['textBoxValues[' + index + '].Value'] = value;
});
$.ajax({
url: '#Url.Action("HandleRequest")',
type: 'POST',
traditional: true,
data: data,
sucesss: function (result) {
alert('Success');
}
})
}

Iterating over a ajax-returned list with $.each - Element is always null

I have the following C# code in my API-controller:
public JsonResult GetProjects()
{
List<ProjectItem> list = ProjectItem.Get();
return new JsonResult() {Data = list, JsonRequestBehavior = JsonRequestBehavior.AllowGet};;
}
I stepped through this code and found out that the list contains elements on this point. But in the Ajax-call I'm calling the code I try to iterate over the single elements with Jquery and try to use them. But the elements are always null.
Typescript Ajax-Call:
$.ajax({
url: "/api//MyControllerName",
type: "GET",
cache:false,
dataType: "json",
success: (result) => {
base.projects.removeAll();
$.each(result, (index: number, element: any) => {
//Here the element from the list should be used, but it is always null
});
});
}
});
What is wrong with this code?
Okay, found the solution to my problem myself:
I tried to iterate over the result, but I have to iterate over the Data-Property of the result.
With this code it works:
$.each(result.Data, (index: number, element: any) => {
//Element is defined
}

Passing IEnumerable parameter to WebAPI

I'm getting started with WebAPI and for the most part all is going well. I'm running into a problem with one particular function. This one differs from the other because it's only parameter is of type IEnumerable.
I've set a breakpoint on the first line of the Post() function and I'm hitting the function but the "values" parameter ALWAYS has a count of 0. I verified that the parameter going in on the client side does, in fact, contain an array of integers. If I remove the [FromUri] attribute, the 'values' parameter is NULL instead of a count of 0.
How do I get my array of integers to come through on my WebAPI function?
Here's the WebAPI function:
[System.Web.Mvc.HttpPost]
public void Post([FromUri] IEnumerable<int> values)
{
if (values == null || !values.Any()) return;
int sortorder = 1;
foreach (int photoId in values)
{
_horseRepository.UpdateSortOrder(photoId, sortorder);
sortorder++;
}
}
Here's the AJAX call (this is using the jQuery UI Sortable feature):
$(".sortable").sortable({
update: function (event, ui) {
var newArray = $(".sortable").sortable("toArray");
$.ajax({
url: '/api/photo',
type: 'POST',
contentType: 'application/json, charset=utf-8',
async: true,
dataType: 'json',
data: JSON.stringify(newArray),
complete: function (data) { }
});
}
});
contentType: 'application/json, charset=utf-8',
should become (the separator between the content type and the charset is a semicolon, not a comma):
contentType: 'application/json; charset=utf-8',
and:
public void Post([FromUri] IEnumerable<int> values)
should become (there are no Uri parameters in a POST request):
public void Post(IEnumerable<int> values)
Now you are good to go assuming that newArray (which you haven't shown here) is an array of integers:
newArray = [ 1, 2, 3 ]

asp.net mvc3 return multiple json list

Im asp.net mvc3 c# code returns json list like this:
return Json(new { name = UserNames, imageUrl = ImageUrls });
UserNames and ImageUrls are both List<string> types
And this is my javascript
function StartSearch(text) {
$.ajax({
url: '/Shared/Search',
type: 'POST',
data: { SearchText: text },
dataType: 'json',
success: function (result) {
$.each(result, function (i, item) {
alert(result[i].name);
});
}
});
}
How I can get names and ImageUrls?
Thanks
Access name as a property of result like this result.name[i]
Essentially, result will contain name and imageUrl which are both arrays, just like you have defined in your anonymous type, so your code should be modified like this to display an alert for each name in the name array
function StartSearch(text) {
$.ajax({
url: '/Shared/Search',
type: 'POST',
data: { SearchText: text },
dataType: 'json',
success: function (result) {
$.each(result.name, function (i, item) {
alert(item);
});
}
});
}
as $each iterates over the items in the name array, it will pass the item to the second parameter of your call back, i.e. item.
so
$.each(result.name, function (i, item) {
alert(item);
});
will popup each name.
Notes:
You may want to change the properties on your anonymous type to reflect that they are a collection:
return Json(new { UserNames = UserNames, ImageUrls = ImageUrls });
this way it will make more sense when you iterate over them in your success function.
As AlfalfaStrange pointed out, I didn't demonstrate how you might access both arrays. Which made me think, what is the relationship between user names and image urls?
Is this a list of images for a user? Maybe what you should consider is creating a specific model for this. For instance, UserDisplayModel:
public class UserDisplayModel
{
public string UserName {get;set;}
public string ImageUrl {get;set;}
}
In your controller return a list of UserDisplayModels. If this is the case, you'll have to rethink why they are two separate lists in the first place. Maybe ImageUrl should be a field on the User table.
So now, when you're returning a single list, e.g.
List<UserDisplayModel> users = //get users from db
return Json(new { Users = Users});
you can iterate them in one go in js code:
$.each(result.Users, function (i, item) {
alert(item.Name);
alert(item.ImageUrl);
});
This alerts the value of Name from each record of each list.
$.each(result, function (i, item) {
for (var x = 0; x < result.FirstList.length; x++) {
alert(result.FirstList[x].Name);
alert(result.SecondList[x].Name);
}
});
This assumes your Json response if formed correctly. Like this:
return Json(new { FirstList = results, SecondList = otherResults }, JsonRequestBehavior.AllowGet);
But as a side note, I see other problems with your code that you need to address
You're actually not performing a POST, you're searching based on input. Change POST to GET in your Ajax call
Change your action return line to allow for the get and make sure your are returning a JsonResult.
Naming conventions for C# method parameters call for Pascal-casing. Use a lowercase letter for first character
public JsonResult Search(string searchText) {
....
return Json(new { name = UserNames, imageUrl = ImageUrls }, JsonRequestBehavior.AllowGet);
}

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