Date:
model.Date) %>--%> // Should I use this as Input type?
Number#:
Comment
I am trying to get these three fields on the screen while user enters I am retreving the user enter data on front end.. when I am debugging I am not seeing these fields..
On the view I am using beginForm
<% using (Html.BeginForm("Update", "Home", FormMethod.Post, new { #id = "id" }))
{ %>
my method..
public JsonResult Update(StudentInfo info)
{
///Update
return Json(Status.ToString());
}
when I see in info I am not getting these three fields..
can any one help me out thanks
You are returning a JsonResult but doing as Http post (Html.BeginForm). If you want to use a full form post then return a ActionResult.
public ActionResult Index()
{
// Add action logic here
return View();
}
you can call void controller
It makes no sense that you're returning a JsonResult from a HTML Post.
Do this instead.
[HttpPost]
public ActionResult Update(StudentInfo info)
{
///Update
if (updateWorked)
return View("Success", status);
}
You use JsonResult when you want to call a controller that returns JSON data, in order to display this data somewhere on your page.
A useful scenario for JsonResult in your scenario would be returning a json list of Students, executed from a click event maybe (call in JavaScript/jQuery).
Calling an action method on a HTTP Post which returns a JsonResult of a single string (not real JSON) makes no sense.
Related
Can i send to the action method new record and then get the new id by the same method
public class HomeController : Controller
{
[HttpGet]
[HttpPost]
public JsonResult _sendConfirmation'(string subject,string mail)
{
Some Code--Some Code---Some Code
return Json(new { Success = true, id = newCreatedMailId });
}
}
Getting the id by jquery
$.getJSON('/Mails/_sendConfirmation', function (comingData) {
alert("success" + data);
jQuery.get('/Mails/_getNewMailSendConfirmation', { id: comingData }, function (data) {
jQuery('#myModal').modal('show');
jQuery('#myModal .modal-body').html(data);
});
enter code here
So your Ajax request is looking for an action named _sendConfirmation on your Mails controller and not finding it but you've chose. To just show us your home controller index action so we have no idea if the appropriate controller exists or not with that.
As far as having it decorated with a get and a post, when you do this you are essentially telling the action to look for data on the request in two different places which will most likely not end well for you unless you plan on doing that switch logic yourself inside the action. Your code would probably be a bit less error prone if you seperated the action and once extracted the data, you call the same helper methods to work your data.
I'm trying this code:-
If no query string supplied to the Index Method then render a Branch Locator View. When a Branch Id is selected in that View, post back to a Redirect To Route Result OR Action Result method and then redirect back to Index with a query string of the selected Branch Id.
I can run through the code successfully without and then with the query string.
I even run through the Index View and can see the Model working however, the Index View does not render, the Branch Selector View remains. Network developer tools shows the correct URL with query string correctly in place when doing the Redirect.
(NOTE: Both methods are on the same controller).
If I add the same query string directly in the Browser address bar it works fine!
I have this code:
[HttpGet]
public ActionResult Index()
{
var querystringbranchId = Request.QueryString["branchId"];
if(!string.IsNullOrEmpty(querystringId))
{
....do stuff like build a model using the branchId...
return View(Model);
}
return View("BranchSelector")
}
[HttpPost]
public RedirectToRouteResult BranchDetails(FormCollection formCollection)
{
var querystringBranchId = formCollection["BranchList"];
var branchId = int.Parse(querystringBranchId);
return RedirectToAction("Index", new { branchId });
}
Try using strongly typed model on the post, and specifying the param as an actual param - Using View models is going to be much better for you.
I have tested the below - It seemed to work as expected for me:
[HttpGet]
public ActionResult Index(int? branchId)
{
if (branchId.HasValue)
{
return View(branchId);
}
return View("BranchSelector");
}
[HttpPost]
public RedirectToRouteResult BranchDetails(MyModel myModel)
{
return RedirectToAction("Index", new { myModel.BranchId });
}
public class MyModel
{
public int BranchId { get; set; }
}
The View:
<div>
#using (Html.BeginForm("BranchDetails", "Home", FormMethod.Post))
{
#Html.TextBox("BranchId","123")
<input type="submit" value="Go"/>
}
</div>
#MichaelLake Thanks to your post I found the problem. I tried your code and sure enough it works as expected. I didn't mention I was using a Kendo Combobox control (!) loaded with the branches. I didn't mention that as the actual data I needed was available in the post method so, thought the issue was with the Controller methods. I had the Kendo control name as BranchList, I changed it to BranchId and it now works with the original code as expected! The Kendo name becomes the element Id and has to match to work.
Many Thanks!
This will work for you. Cheers :D
return RedirectToAction("Index", "ControllerName", new { branchId = branchId});
Scenario: How to update a model?
ASP MVC 6
I am trying to update a model. For passing the model information to the client(browser/app) I am using the DTO.
Question 1: For updating, should I post the whole object back?
Question 2: Is there a way I can easily pass only the information that is updated? If yes, how?
Question 3: Can I use JSON Patch for updation?
Question 2: Is there a way I can easily pass only the information that
is updated? If yes, how?
Yes. You should create a view model which should have only those properties needed for the view.
Let's assume your use case is to build a view which allows user to edit only their last name.
public class EditUserViewModel
{
public int Id {set;get;}
public string LastName {set;get;}
}
And in your Get
public ActionResult Edit(int id)
{
var user = yourUserRepository.GetUser(id);
if(user!=null)
{
var v = new EditUserViewModel { Id=id,LastName=user.LastName};
return View(v);
}
return View("NotFound");
}
And the view
#model EditUserViewModel
#using(Html.BeginForm())
{
#Html.TextBoxFor(s=>S.LastName)
#Html.HiddenFor(s=>s.Id)
<input type="submit" id="saveBtn" />
}
and your HttpPost action
[HttpPost]
public ActionResult Edit(EditUserViewModel model)
{
// Since you know you want to update the LastName only,
// read model.LastName and use that
var existingUser = yourUserRepository.GetUser(model.Id);
existingUser.LastName = model.LastName;
yourUserRepository.Save();
// TO DO: redirect to success page
}
Assuming yourUserRepository is an object of your data access classes abstraction.
Question 1: For updating, should I post the whole object back?
Depends on what you want from the end user. With this view model approach, It is going to post only the Id and LastName and that is our use case.
Can I use JSON Patch for updating?
Since you are only sending the data which needs to be updated (partial data), you should be fine.
If you want,you may simply serialize your form data(which has only Id and LastName) and use jQuery post method to send it to your server.
$(function(){
$("#saveBtn").click(function(e){
e.preventDefault(); //prevent default form submit
var _form=$(this).closest("form");
$.post(_form.attr("action"),_form.serialize(),function(res){
//do something with the response.
});
});
});
To prevent overposting, you can use a binding whitelist using Bind attribute on your HttpPost action method. But the safest strategy is to use a view model class that exactly matches what the client is allowed to send.
Instead of this
UpdateModel(model);
You now can call this
await TryUpdateModelAsync(model);
I have an index action on a controller as follows...
public ActionResult Index(string errorMsg = "")
{
//do stuff
ViewBag.ErrorMsg=erorMsg;
return View();
}
I have another action that is an http post for Index.
When there is something wrong I want to reload the Index page and show the error...
I have my view already conditionally showing errorMsg. But I cannot figure out how to call Index and pass in the error string?
Typically, you'd just share the view between the two actions. I'm guessing you have actions that look something like this (the more info you provide about what index does, the better my example will be):
public ActionResult Index()
{
return View();
}
[HttpPost, ActionName("Index")]
public ActionResult IndexPost()
{
if (!ModelState.IsValid)
{
ViewBag.ErrorMsg = "Your error message"; // i don't know what your error condition is, so I'm just using a typical example, where the model, which you didn't specify in your question, is valid.
}
return View("Index");
}
And Index.cshtml
#if(!string.IsNullOrEmpty(ViewBag.ErrorMsg))
{
#ViewBag.ErrorMsg
}
#using(Html.BeginForm())
{
<!-- your form here. I'll just scaffold the editor since I don't know what your view model is -->
#Html.EditorForModel()
<button type="Submit">Submit</button>
}
If I understand you correctly you just need to hit the url with the errorMsg in the query string:
/*controllername*/index?errorMsg=*errormessage*
However, when there is something wrong you don't necessarily need to reload the page. Seems like you might be approaching this in the wrong way..?
You can use RedirectToAction to redirect to the page, with a querystring for errorMsg value.
[HttpPost]
public ActionResult Index(YourViewModel model)
{
try
{
//try to save and then redirect (PRG pattern)
}
catch(Exception ex)
{
//Make sure you log the error message for future analysis
return RedirectToAction("Index",new { errorMs="something"}
}
}
RedirectToAction issues a GET request. So your form values will be gone, because HTTP is stateless. If you want to keep the form values as it is in the form, return the posted viewmodel object again. I would get rid of ViewBag and add a new property called ErrorMsg to my ViewModel and set the value of that.
[HttpPost]
public ActionResult Index(YourViewModel model)
{
try
{
//try to save and then redirect (PRG pattern)
}
catch(Exception ex)
{
//Make sure you log the error message for future analysis
model.ErrorMsg="some error";
return View(model);
}
}
and in the view you can check this model property and show the message to user.
I am working on an MVC application and I have an index view where I pass model from controller to index view. The index action has no parameters. Now On view I have a jquery calendar. I want to change all the data on view when a date is selected. do I need to use different action method for this as current action method doesn't have parameter. or I can use same ? Please suggest
Sounds like you need a DateTime parameter on that index view. You can then handle the case where it is null in the action:
public ActionResult Index(DateTime dateTime)
{
if (dateTime == null)
//Do default view
else
//Use date for view
}
Use a client-side event handler on the calendar, and call a different action on the controller via jQuery.ajax()
http://api.jquery.com/jQuery.ajax/
You can create the same Action method to handle both:
[HttpGet]
public ActionResult DoThis() { }
[HttpPost]
public ActionResult DoThis(FormCollection data) { }
It can be the same action, but it has to be a different action handler to handle the post to the server, where the post is from a form or a JQuery call.