The following is an example how i am posting data to a controller action in MVC.The data is perfectly populating to my model object and working fine.
var data={};
data.SearchText = 'abc'
data.SearchText1 = 'abcd'
var contentType = 'application/json; charset=utf-8';
$.ajax({
type: 'POST',
cache: false,
contentType: contentType,
url: User/_UserList,
data: JSON.stringify(data),
success: successHandlerFunction,
complete: completeHandlerFunction
});
[HttpPost]
public JsonResult _UserList(SearchViewModel model)
{
var users= "" ; //Get Data from DB ;
return Json(users, JsonRequestBehavior.AllowGet);
}
But in case of an exception i am trying to fetch value of model
public void OnException(ExceptionContext filterContext)
{
//filterContext.HttpContext.Request.Form -- is not giving any value
//filterContext.HttpContext.Request.QueryString -- is also having no value
//filterContext.HttpContext.Request.Params -- also no value about model
}
Can anybody give me a clue why the above piece of code not working
Sorry - can't comment your answer, so placing a new answer.
The solution is right - you should make the contentType as 'application/x-www-form-urlencoded'. The reason is clearly described here: HttpRequest.Form Property
The Form property is populated when the HTTP request Content-Type value is either "application/x-www-form-urlencoded" or "multipart/form-data".
As for 'JSON.stringify(data),' - that will make one string from the dictionary actually and in this case HttpRequest.Form cannot be populated as it requires a dictionary, basically, just 'data'.
By Changing the contentType from 'application/json; charset=utf-8' to
'application/x-www-form-urlencoded' the HttpContext.Request.Form started populating the value.We also need to remove the JSON.stringify while passing the data.
If we post the data with contentType 'application/json; charset=utf-8' .And from the request object we need to retrieve the Json Contents then we can use the following piece of code
private string GetJsonContents(System.Web.HttpRequestBase Request)
{
string JsonContents = string.Empty;
try
{
using (Stream receiveStream = Request.InputStream)
{
using (StreamReader readStream = new StreamReader(receiveStream))
{
receiveStream.Seek(0, System.IO.SeekOrigin.Begin);
JsonContents = readStream.ReadToEnd();
}
}
}
catch
{
}
return JsonContents;
}
Then we can use the following code to get the JSON Object
string requestData = GetJsonContents(HttpContext.Current.Request);
dynamic jsonObject = JsonConvert.DeserializeObject<dynamic>(requestData);//using Newtonsoft dll
Related
My app is made in ASP.NET MVC 5. User can use search form which is displaying filtered data. Now I want to add button which will export displayed data.
To do this I am sending Search object to view and save it in html. Now When clicking export button I want to pass this object to controller, get data from database using this Search object and save results as text.
The thing is I cant bind json to c# object. Thats my view:
<div id="originalForm" style="visibility:hidden">
#Html.Raw(Newtonsoft.Json.JsonConvert.SerializeObject(Model))
</div>
This is my ajax code:
function exportRaportToCsv() {
var $formData = $('#originalForm').text();
var allIds = getCheckedIds();
var dataToSend = JSON.stringify({
ids: allIds,
search: $formData
});
$.ajax({
type: "POST",
url: '#Url.Action("ExportToCsv", "BankCosts")',
data: dataToSend,
contentType: "application/json; charset=utf-8",
success: function (datar) {
window.location = '/BankCosts/Download?fileGuid=' + response.FileGuid
+ '&filename=' + response.FileName;
},
error: function (xhr) {
},
});
}
And this is my controller:
[HttpPost]
public ActionResult ExportToCsv(string[] ids, Search search)
{
// search is null here
}
When I spy sending data with Fiddler I can see, that I am passing this:
{"ids":[],"search":"\n {\"ID\":0,\"DateFrom\":\"2018-06-23T00:00:00\",\"DateTo\":\"2018-06-25T00:00:00\",\"hasUnrecognizedStatus\":false,\"skippedSearchResults\":0,\"paginationLimit\":100}\n"}
I think it is worth to mention, that ids is properly passed. If it contains data, that data is passed. I think the problem is that I have \ in my json. How can I remove this? Is there something wrong with my ajax?
When I use console.log to print $formData I can see that \ characters are gone and it looks better:
{"ID":0,"DateFrom":"2018-06-23T00:00:00","DateTo":"2018-06-25T00:00:00","hasUnrecognizedStatus":false,"skippedSearchResults":0,"paginationLimit":100}
[HttpPost]
public ActionResult ExportToCsv(string[] ids,[FromBody]Search search)
{
}
Try adding FromBody if your Search model is ok it should work.
based on your comments, I think that search object already stringified, so you don't need to stringify it.
just make your json like this
var dataToSend = {
"ids": allIds,
"search": $formData
};
Use JSON.parse() to transforms JSON string to a JavaScript object. Your $('#originalForm').text() is a JSON string actually.
var $formData = JSON.parse($('#originalForm').text());
var allIds = getCheckedIds();
var dataToSend = JSON.stringify({
ids: allIds,
search: $formData
});
In your case, $formData is a string (JSON string actually). So JSON.stringify() again trying to convert to JSON string which is already a JSON string that's causing unnecessary '/' character in form data that you are posting.
Make sure to set the content type to 'application/json' in ajax call properties Otherwise MVC model binder will not be able to map and fill .NET model from JSON posted data.
contentType: "application/json; charset=utf-8",
Since you are using
JSON.stringify
the search value posted in string format not object
Search
so
Try replace your controller with this
[HttpPost]
public ActionResult ExportToCsv(string[] ids, string search)
{
//then deserialize search json like
Search objSearch = JsonConvert.DeserializeObject<Search>(search);
}
or
[HttpPost]
public ActionResult ExportToCsv(string[] ids, JObject search)
{
//then deserialize search json like
Search objSearch = JsonConvert.DeserializeObject<Search >
(dataModel["search"].ToString());
}
View
$.ajax({
type: "POST",
url: '#Url.Action("ExportToCsv", "BankCosts")',
data:{ids= allIds.toString(),search:JSON.stringify($formData)}
contentType: "application/json; charset=utf-8",
success: function (datar) {
window.location = '/BankCosts/Download?fileGuid=' + response.FileGuid
+ '&filename=' + response.FileName;
},
error: function (xhr) {
},
});
I'm trying to post some JSON to a web service. The web-service is executed but there's no data available.
The jQuery looks like this :
var json = {"Results": results};
var jsonArray=JSON.stringify(json);
$.ajax({
type: "POST",
contentType: "application/json; charset=utf-8",
url: requestURL,
data: jsonArray ,
dataType: "json",
success: function (data) { TCG.QUE.processSaveButtonSucceeded(data); },
error: function (data) { TCG.QUE.processSaveButtonFailed(data); }
});
And the webservice implemented in a controller looks like this :
public HttpResponseMessage Post([FromBody]string value)
{
object o1 = Request.Content;
HttpResponseMessage r = new HttpResponseMessage(HttpStatusCode.OK);
return r;
}
If I take out the [FromBody] directive then I get a 404. If I leave it in the code is executed but the value of the value argument is null.
I thought the [FromBody] directive meant the data was contained in the Request object but if it is I can't find it .
Would appreciate any suggestions so that I can access the JSON from the client within the Post method.
UPDATE:
I just re-read this : http://www.asp.net/web-api/overview/formats-and-model-binding/parameter-binding-in-aspnet-web-api which made me wonder whether the name I was giving the JSON blog client side should correspond to the name of the argument on which the [FromBody] is applied so I changed the name of the argument from value to Results but still the value within the Post method is null.
RESOLUTION
After reading the blog post referred to by Prashanth Thurairatnam I changed my method to be like this and it works :
public HttpResponseMessage Post([FromBody]JToken jsonbody)
{
// Process the jsonbody
return new HttpResponseMessage(HttpStatusCode.Created);
}
.
Not sure what you are passing into results. Ran into this blog. You may want to give it a go. The blog talks on passing the data as JSON object/ array (you may want to try without JSON.stringify)
I have a C#.net method as given below
public string jsonTest()
{
List<string> list = new List<string>();
list.Add("aa");
list.Add("bb");
list.Add("cc");
string output = JsonConvert.SerializeObject(list);
return output;
}
Here eventhough Im creating a Json object by using JsonConvert.SerializeObject I am getting a string (since return type is string).
Can I do like below by using a return type JsonResult (or somthing like that) something like what we can do in MVC?
return Json(new { data = list }, JsonRequestBehavior.AllowGet);
Is it possible to create a Json data in asp.net?
In client side I'm using an ajax call to get data from jsonTest().
$.ajax({
type: 'GET',
url: "test.aspx", //In test.aspx pageload calling jsonTest()
dataType: 'json',
success: function (data) {
alert(data);
},
error: function (data) {
alert("In error");
}
});
When I'm giving dataType: 'json', it will go to error part (Since the ajax expects json data but it gets string). Thats why I want to parse it as a json object in server side.
If ASP.NET,
string output = JsonConvert.SerializeObject(list);
Response.Clear();
Response.ContentType = "application/json; charset=utf-8";
Response.Write(output);
Response.End();
There is nothing called a JSON object. The SerializeObject method returns a string because JSON is nothing more than a string value which follows specific rules.
To return JSON to the browser all you need to do is:
Response.ContentType = "application/json; charset=utf-8";
Response.Write(jsonTest());
Response.End();
I'm going to assume you're trying to create a WebMethod for consumption by a JavaScript XHR call or similiar:
ASP.NET will auto-serialize to JSON for POST requests only (using ASMX or so called "Page Methods"). WCF and WebAPI do not require the POST method, but do require some configuration.
[WebMethod]
public static List<Task> TasksGet(string projectId) {
return MyNamespace.Tasks.GetForProject(projectId);
}
The result your JS call sees would be something like:
{"d": [{
"__type": "MyNamespace.Task",
"id": 1,
"description": "This is my first task"
}, {
"__type": "MyNamespace.Task",
"id": 2,
"description": "This is my second task"
}, {
....etc etc
}
]}
No need to mess around w/ the JsonSerializer class directly.
Also make sure your request headers are set correctly:
Content-Accept: application/json;charset=UTF8
Json is just string data. It is how that string is interpreted. So the fact that it is returning a string is correct. You mentioned ASP.Net. Are you using ASP.Net webforms and looking for a way to return that JSON to the front side?
I don´t know why my parameter "ParametroFiltro Filtro" is getting null, the other parameters "page" and "pageSize" is getting OK.
public class ParametroFiltro
{
public string Codigo { get; set; }
public string Descricao { get; set; }
}
My ApiController Get method:
public PagedDataModel<ParametroDTO> Get(ParametroFiltro Filtro, int page, int pageSize)
My ajax call:
var fullUrl = "/api/" + self.Api;
$.ajax({
url: fullUrl,
type: 'GET',
dataType: 'json',
data: { Filtro: { Codigo: '_1', Descricao: 'TESTE' }, page: 1, pageSize: 10 },
success: function (result) {
alert(result.Data.length);
self.Parametros(result.Data);
}
});
You are trying to send a complex object with GET method. The reason this is failing is that GET method can't have a body and all the values are being encoded into the URL. You can make this work by using [FromUri], but first you need to change your client side code:
$.ajax({
url: fullUrl,
type: 'GET',
dataType: 'json',
data: { Codigo: '_1', Descricao: 'TESTE', page: 1, pageSize: 10 },
success: function (result) {
alert(result.Data.length);
self.Parametros(result.Data);
}
});
This way [FromUri] will be able to pick up your complex object properties directly from the URL if you change your action method like this:
public PagedDataModel<ParametroDTO> Get([FromUri]ParametroFiltro Filtro, int page, int pageSize)
Your previous approach would rather work with POST method which can have a body (but you would still need to use JSON.stringify() to format body as JSON).
Provide the contentType property when you make the ajax call. Use JSON.stringify method to build the JSON data to post. change the type to POST and MVC Model binding will bind the posted data to your class object.
var filter = { "Filtro": { "Codigo": "_1", "Descricao": "TESTE" },
"page": "1", "pageSize": "10" };
$.ajax({
url: fullUrl,
type: 'POST',
dataType: 'json',
contentType: 'application/json',
data: JSON.stringify(filter),
success: function (result) {
alert(result.Data.length);
self.Parametros(result.Data);
}
});
It's also possible to access POST variables via a Newtonsoft.Json.Linq JObject.
For example, this POST:
$.ajax({
type: 'POST',
url: 'URL',
data: { 'Note': note, 'Story': story },
dataType: 'text',
success: function (data) { }
});
Can be accessed in an APIController like so:
public void Update([FromBody]JObject data)
{
var Note = (String)data["Note"];
var Story = (String)data["Story"];
}
If you append json data to query string, and parse it later in web api side. you can parse complex object too. It's useful rather than post json object, espeicaly in some special httpget requirement case.
//javascript file
var data = { UserID: "10", UserName: "Long", AppInstanceID: "100", ProcessGUID: "BF1CC2EB-D9BD-45FD-BF87-939DD8FF9071" };
var request = JSON.stringify(data);
request = encodeURIComponent(request);
doAjaxGet("/ProductWebApi/api/Workflow/StartProcess?data=", request, function (result) {
window.console.log(result);
});
//webapi file:
[HttpGet]
public ResponseResult StartProcess()
{
dynamic queryJson = ParseHttpGetJson(Request.RequestUri.Query);
int appInstanceID = int.Parse(queryJson.AppInstanceID.Value);
Guid processGUID = Guid.Parse(queryJson.ProcessGUID.Value);
int userID = int.Parse(queryJson.UserID.Value);
string userName = queryJson.UserName.Value;
}
//utility function:
public static dynamic ParseHttpGetJson(string query)
{
if (!string.IsNullOrEmpty(query))
{
try
{
var json = query.Substring(7, query.Length - 7); //seperate ?data= characters
json = System.Web.HttpUtility.UrlDecode(json);
dynamic queryJson = JsonConvert.DeserializeObject<dynamic>(json);
return queryJson;
}
catch (System.Exception e)
{
throw new ApplicationException("can't deserialize object as wrong string content！", e);
}
}
else
{
return null;
}
}
In .NET Core, the HttpClient sets the transfer-encoding: chunked header by default. This can cause the .NET Web API controller parameters to be null.
To get around this, you'll need to set the ContentLength header explicitly:
var json = JsonConvert.SerializeObject(myObject);
var content = new StringContent(json, Encoding.UTF8, "application/json");
content.Headers.ContentLength = json.Length;
var response = await client.PostAsync("http://my-api.com", content);
SO answer if you already know the transfer-encoding header is the issue: How to disable Chunked Transfer Encoding in ASP.Net C# using HttpClient
Related bug which won't be fixed, which gives some insight into the problem: https://github.com/dotnet/runtime/issues/30283
I'm trying to learn how to make a simple call to the server from Javascript/jQuery. I've been trying to learn and could not find a tutorial with those simple steps.
I want to send a message to the server with two parameters (a DateTime and a String) and get back a DateTime. I want to do that via JSON.
How would the code in the server look like (structure only)?
Is there something special I should do on the server side? And how about security?
How would I implement the call in jQuery?
And how would I handle the result?
I'm most interested on code structure.
Update
I found the answer below great to get me started. However, I recently stumbled upon Full ASP.NET, LINQ, jQuery, JSON, Ajax Tutorial. It's just a fantastic and very didactic step-by-step that I want to share with anyone else who comes across this question in the future.
There are several ways that you can do this; this will serve as a single example.
You could write something like this for your jQuery code:
urlToHandler = 'handler.ashx';
jsonData = '{ "dateStamp":"2010/01/01", "stringParam": "hello" }';
$.ajax({
url: urlToHandler,
data: jsonData,
dataType: 'json',
type: 'POST',
contentType: 'application/json',
success: function(data) {
setAutocompleteData(data.responseDateTime);
},
error: function(data, status, jqXHR) {
alert('There was an error.');
}
}); // end $.ajax
Next, you need to create a "generic handler" in your ASP.net project. In your generic handler, use Request.Form to read the values passed in as json. The code for your generic handler could look something like this:
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
public class handler : IHttpHandler , System.Web.SessionState.IReadOnlySessionState
{
public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "application/json";
DateTime dateStamp = DateTime.Parse((string)Request.Form["dateStamp"]);
string stringParam = (string)Request.Form["stringParam"];
// Your logic here
string json = "{ \"responseDateTime\": \"hello hello there!\" }";
context.Response.Write(json);
}
See how this work out. It will get you started!
Update: I posted this code at the CodeReview StackExchange: https://codereview.stackexchange.com/questions/3208/basic-simple-asp-net-jquery-json-example
If you are using jQuery you could do it with a GET or POST.
$.get ('<url to the service>',
{ dateParam: date, stringParam: 'teststring' },
function(data) {
// your JSON is in data
}
);
$.post ('<url to the service>',
{ dateParam: date, stringParam: 'teststring' },
function(data) {
// your JSON is in data
}
);
Note that the name of the parameters in (e.g. dateParam, stringParam) need to be the same as the name of the parameters your service method is expecting. Also that your service will need to format the result as JSON, the data parameter in the call back will contain anything your service sends back (e.g. text, xml, json, etc).
See the jQuery documentation for $.ajax, $.get, $.post: http://api.jquery.com/jQuery.ajax/, http://api.jquery.com/jQuery.get/, http://api.jquery.com/jQuery.post/
Here sample code using jquery ajax call and on serverside webmethod returns jSon format data.
Jquery :
$(‘#myButton’).on(‘click’,function(){
var aData= [];
aData[0] = “2010”;
aData[0]=””
var jsonData = JSON.stringify({ aData:aData});
$.ajax({
type: "POST",
url: "Ajax_function/myfunction.asmx/getListOfCars", //getListOfCars is my webmethod
data: jsonData,
contentType: "application/json; charset=utf-8",
dataType: "json", // dataType is json format
success: OnSuccess,
error: OnErrorCall
});
function OnSuccess(response.d)) {
console.log(response.d)
}
function OnErrorCall(response)) { console.log(error); }
});
Codebehind : Here a webmethod which is returning json format data i.e list of cars
[webmethod]
public List<Cars> getListOfCars(list<string> aData)
{
SqlDataReader dr;
List<Cars> carList = new List<Cars>();
using (SqlConnection con = new SqlConnection(cn.ConnectionString))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = "spGetCars";
cmd.CommandType = CommandType.StoredProcedure;
cmd.Connection = con;
cmd.Parameters.AddWithValue("#makeYear", aData[0]);
con.Open();
dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
if (dr.HasRows)
{
while (dr.Read())
{
string carname=dr[“carName”].toString();
string carrating=dr[“carRating”].toString();
string makingyear=dr[“carYear”].toString();
carList .Add(new Cars{carName=carname,carRating=carrating,carYear=makingyear});
}
}
}
}
return carList
}
//Created a class
Public class Cars {
public string carName;
public string carRating;
public string carYear;
}