We Keep Coding

How to send a JavaScript object on the server side (ASP NET MVC)?

Below is the relevant code (JS+jQuery on the client side):
function getuser(username, password) {
var user = new Object();
user.constructor();
user.username = username;
user.password = password;
//....
$("#a1").click(function () {
var u = getuser($("#username").val(), $("#password").val());
if (u == false) {
alert("error");
} else {
//....
}
});
}
The question is how to send var u to a session on the server side?

You can use ajax to accomplish this. Something like:
$.ajax({
url: "/Controller/Action/",
data: {
u: u
},
cache: false,
type: "POST",
dataType: "html",
success: function (data) {
//handle response from server
}
});
Then have a controller action to receive the data:
[HttpPost]
public ActionResult Action(string u)
{
try
{
//do work
}
catch (Exception ex)
{
//handle exceptions
}
}
Note that /controller/action will be specific to where youre posting the data to in your project

See the documentation
For example:
If you just want to do a simple post the following may suit your needs:
var user = getUser(username, password);
$.post(yourserverurl, user, function(response){console.log("iam a response from the server")});
As the documentation says:
This is a shorthand to the equivalent Ajax function:
$.ajax({
type: "POST",
url: url,
data: data,
success: success,
dataType: dataType
});
So In your example:
$.ajax({
type: "POST",
url: "/mycontroller/myaction",
data: {user: getUser(username, password)},
success: function(responseFromServer){//handleResponseHere},
error: function(xhr){//handleyourerrorsHere}
dataType: yourdatatype
});

Combining Ajax posts with MVC controllers and redirects

I'm trying to get my server-side code to play nicely with some page templates we got from a design agency. All is good except that I'm struggling to implement the correct behaviour with the results of the form submission.
What should happen is, if the form submits successfully, some JQuery is triggered to animate into a success message. If not, the user should be redirected to an error page.
Here's the form submit script:
$.ajax({
type: 'POST',
data: JSON.stringify(userObject),
url: submitFormUrl,
contentType: 'application/json; charset=utf-8',
cache: 'false',
dataType: 'json',
success: function (data) {
if(data.Success){
console.log('success');
$('.thanks-msg').fadeIn(1000);
$('#market-message').hide();
}else{
console.log('Error');
}
}
});
And here's the controller action that it posts to:
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Register(User userObject)
{
bool userExists;
try
{
if (ModelState.IsValid)
{
userExists = InsertUser(userObject); //calls a sproc
}
else
{
return CollectValidationErrors(); // collects all validation errors into a string
}
}
catch(Exception ex)
{
ViewBag.ErrorMessage = "Sorry! There has been an error " + ex.Message;
return Json(new { result = "Redirect", url = Url.Action("Error", "Home") });
}
if(userExists)
{
ViewBag.ErrorMessage = "This user already exists";
return Json(new { result = "Redirect", url = Url.Action("Error", "Home") });
}
return Json(new { success = true }, JsonRequestBehavior.AllowGet);
}
What happens is that the form submission is received and the code inside executed successfully. But if an error state is returned, there's no redirect.
What am I doing wrong?

Try to use error property of ajax call:
$.ajax({
type: 'POST',
data: JSON.stringify(userObject),
url: submitFormUrl,
contentType: 'application/json; charset=utf-8',
cache: 'false',
dataType: 'json',
error: function (XMLHttpRequest, textStatus, errorThrown) {
//Do Something
},
success: function (data) {
if(data.Success){
console.log('success');
$('.thanks-msg').fadeIn(1000);
$('#market-message').hide();
}else{
console.log('Error');
}
}
});

You do not send an error.
You can throw an Exception (forces HTTP Status 500 Internal Server Error) in the Controller Action. It will result that the success is not invoked, but the error function of ajax.
$.ajax({
type: 'POST',
data: JSON.stringify(userObject),
url: submitFormUrl,
contentType: 'application/json; charset=utf-8',
cache: 'false',
dataType: 'json',
success: function (data) {
if(data.Success){
console.log('success');
$('.thanks-msg').fadeIn(1000);
$('#market-message').hide();
}else{
console.log('Error');
}
},
error: function(function (xhr, status, errorThrown)){
// Do Redirect
}
});

Calling a controller method via javascript

I have an ASP.NET application where I am invoking a controller methode from JavaScript. My JavaScript code looks like this:
function OnNodeClick(s, e) {
$.ajax({
type: "POST",
url: '#Url.Action("DeviceManifests", "Home")',
data: { selectedRepo: e.node.name },
success: function (data) {
if (data != null) {
$('#GridView').html(data);
}
},
error: function (e) {
alert(e.responseText);
}
});
}
This calls the Home controller's DeviceManifests() method.
This is what the method looks like:
public ActionResult DeviceManifests(Guid selectedRepo)
{
var repoItem = mock.GetRepoItem(selectedRepo);
return View("Delete", repoItem.childs);
}
The method gets invoked but the problem is the Delete-View doesn't get rendered. There's no error, just nothing happens.
How can I update my code to get my desired behaviour?

Do like below code so if you have error you will have it in alert box or success result will rendered in DOM
$.ajax({
type: "GET",
contentType: "application/json; charset=utf-8",
url: '#Url.Action("DeviceManifests", "Home")',
data: { selectedRepo: e.node.name },
dataType: "html",
success: function (data) {
if (data != null) {
$('#someElement').html(data);
}
}
},
error: function (e) {
alert(e.responseText);
}
});

You can do the redirect in the javascript side.
function OnNodeClick(s, e) {
$.ajax({
type: "GET ",
url: '#Url.Action("DeviceManifests", "Home")',
data: { selectedRepo: e.node.name },
success: function (msg)
{
window.location = msg.newLoc;
}
});
}
Make sure you include the redirect url in action and return JsonResult and not ActionResult. I'd also include pass the guid so that the destination Action and let it look up the data.

C# Web method is not calling in javascript

i create a web method and now i'm calling this in my java script file but it give an path error,it is not able to find path what i'm giving ..
Web method code is :
[System.Web.Services.WebMethod]
public static int ItemCount(string itemId)
{
int val = 0;
Item itm = Sitecore.Context.Database.GetItem(itemId);
val = itm.Children.Count;
return val;
}
java script function calling like as:
function GetItemCount(itemId) {
var funRes = "";
debugger;
try {
if (itemId != null) {
jQuery.ajax({
cache: false,
type: "POST",
contentType: "application/json; charset=utf-8",
url: "/Views/GetItem.aspx/ItemCount",
data: { itemId: itemId },
dataType: "json",
async: false,
success: function (data) {
funRes = data.result;
},
error: function(err) {
alert(err.responseText);
}
});
}
} catch (ex) {
alert(ex.message);
}
return funRes;}
while i'm giving exact path for the C# method class but it's not working give an error on console, can anyone suggest me what i'm missing here..

There are few rules for ajax to work with asp.net.
Your WebMethod should be public and static.
If your WebMethod expects some parameter(s) than these parameter(s) must be passed as data in ajax.
Name of parameter(s) should be same in WebMethod and in data part of ajax.
Data passed from ajax should be in json string.For this you can use JSON.stringify or you will have to surround the values of parameter(s) in quotes.
Please check the below sample ajax call
function CallAjax()
{
$.ajax({
type: "POST",
contentType: "application/json; charset=utf-8",
url: "Default.aspx/CallAjax",
data: JSON.stringify({ name: "Mairaj", value: "12" }),
dataType: "json",
async: false,
success: function (data) {
//your code
},
error: function (err) {
alert(err.responseText);
}
});
}
[WebMethod]
public static List<string> CallAjax(string name,int value)
{
List<string> list = new List<string>();
try
{
list.Add("Mairaj");
list.Add("Ahmad");
list.Add("Minhas");
}
catch (Exception ex)
{
}
return list;
}
EDIT
If you use GET in ajax than you need to enable your webmethod to be called from GET request. Add [System.Web.Script.Services.ScriptMethod(UseHttpGet = true)] on top of WebMetod
[System.Web.Services.WebMethod]
[System.Web.Script.Services.ScriptMethod(UseHttpGet = true)]
public static int ItemCount()

Just Modify the javascript function as below
function GetItemCount(itemId) {
var funRes = "";
debugger;
try {
if (itemId != null) {
jQuery.ajax({
type: "GET",
url: "/Views/GetItem.aspx",
data: 'itemID=' + itemId,
contentType: "application/html",
dataType: "html",
success: function (response) {
funRes= response.result;
}
});
}
} catch (ex) {
alert(ex.message);
}
return funRes;
}

I am not sure it is a solution for every question subject which web method not fire. But I discovered today when there is ' char in the string. Web Method not firing.

Do you need to use two calls - 1 get and 1 post in ajax or can you send data back with the success / failure?

I have the following controller method:
public JsonResult CreateGroup(String GroupName)
{
ApplicationUser user;
var userName = User.Identity.Name;
using (DAL.GDContext context = new DAL.GDContext())
{
user = context.Users.FirstOrDefault(u => u.UserName == userName);
if (user != null)
{
var group = new Group();
group.GroupName = GroupName;
group.Members.Add(user);
context.Groups.Add(group);
context.SaveChanges();
}
}
string result = userName;
return Json(result, JsonRequestBehavior.AllowGet);
}
with the following ajax call:
$(function () {
$('#CreateGroup').on("click", function () {
var groupName = $('#groupname').val();
if (groupName != '') {
$.ajax({
url: '#Url.Action("CreateGroup","AjaxMethods")',
type: "POST",
data: JSON.stringify({ 'GroupName': groupName }),
dataType: "json",
cache: false,
contentType: "application/json; charset=utf-8",
success: function (data) {
alert("success");
CreateGroup(data);
},
error: function () {
alert("An error has occured!!!");
}
});
}
});
The CreateGroup function fails saying "Uncaught ReferenceError: data is not defined"
Do i have to use another Json request - type post - to get the username?

you can do the call without using JSON.stringify. Also your controller method has a cache attribute that may yield more control. Personally, I would use the controller cache control. You are probably getting a cached version of the controller call prior to returning data.
[OutputCache(NoStore = true, Duration = 0)]
public ActionResult CreateGroup(string GroupName)
$.ajax({
url: '#Url.Action("CreateGroup","AjaxMethods")',
type: "POST",
data: { 'GroupName': groupName },
dataType: "json",
traditional: true,
success: function (data, status, xhr ) {
alert("success");
CreateGroup(data);
},
error: function () {
alert("An error has occured!!!");
}
});
NOTE: Update success callback.