How to serialize ZF2 form object to JSON? - ajax

I'm using zf2 form object on the server and ajax code on the client to implement my registration form.
I post the form values in the ajax request, no problem, and the form gets them fine with
$form->setData($request->getPost());
After I validate the form and perform the registration on the server, I want to send the form back to the client, especially if there are errors, so I can show them to the user.
I'm looking for a standard way using zend or any plugin to serialise the form object into JSON format, so I can send it in the response to the AJAX call.
Any idea?

Well what you can do is run the validation on your form and after that you will return your form within a new JsonModel.
Here is a little example of how to handle your controller:
class RegistrationController extends AbstractActionController
{
public function RegisterAction()
{
$form = new RegisterForm();
$form->setInputFilter(new RegisterInputFilter());
if ($this->getRequest()->isPost()) {
$form->setData($this->getRequest()->getPost());
if($form->isValid()) {
// Handle your registration as the form is valid!
// return to some path after registration is complete.
// Show user he registered succesfully, etc. ;)
}
// Checks if the request is from JavaScript
if($this->getRequest()->isXmlHttpRequest()) {
return new JsonModel(array('registerForm' => $form));
}
}
return new ViewModel(array('registerForm' => $form));
}
}
Notice that the form object is holding all the invalid inputs including its message after validation.
I would take another approach just to completely render the ViewModel again so you can display the validation message much easier. On the side you could add Client Side (Javascript) validation as it's much more user-friendly, but that is just some fancy shizzle I would do ;) In case of rendering the ViewModel:
use Zend\View\Renderer\PhpRenderer;
if($this->getRequest()->isXmlHttpRequest()) {
$renderer = new PhpRenderer;
$registerViewModel = new ViewMOdel();
$registerViewModel->setTemplate('view/register.phtml');
return new JsonModel(array('registerViewModel' => $renderer->render($registerViewModel));
}
Note that not setting a template to your viewModel will result in ZF2 getting the default of the action (view/moduleName/registration/register.phtml) you are in! So in your case you don't need to use PhpRenderrer::setTemplate(). But I just hand it to you so you can change it if you are using any other file.
So now you will receive Json from our controller, in your javascript. Retrieve the new ViewModel from Json and remove the old ViewModel and replace it with the new. By removing the old, you also remove any Javascript that is bound to any element within the viewModel, so you might set the events on your body within your javascript or have it on your attributes in Form/RegistrationForm.
Hope this pushes you in the right direction.

Related

handle direct url with history api in asp.mvc

I have my site like http://mysite.com/ and on the index page i have search box and for the result i am using jqgrid. When user click row in the jqgrid row I am taking data from cells and do ajax call to server and fetch json data and once data arrived I hide the search box and jqgrid and show another div which is I kept for result. In short, user will be on the same page just div's hide/show.
Now I have seen history api and used pushState and popstate so my url becomes in the addressbar like http://mysite.com/controller/action/para1/para2 (here para1 and para2 are the parameters i am passing to action). Everything is ok so far.
Now the problem is if I copy this URL "http://mysite.com/controller/action/para1/para2" and if I open this with let's say different browser and hit enter it display just json data. So, I am confused that how to handle when user directly use that url in controller.
I was thinking to check in the controller action if the request is AJAX then return json data otherwise full page, is that right approach? OR something on the client side we have so that it load the same way as earlier.
Thanks
if I copy this URL "http://mysite.com/controller/action/para1/para2" and if I open this with let's say different browser and hit enter it display just json data.
it only display json data because its ajax call only so how to deal with that so that it also display the same page even user directly access the url.
I think what you're looking for is Request.IsAjaxRequest():
public class FooController : Controller {
public ActionResult GetFoo(int id) {
var model = _fooService.Get(id);
if (Request.IsAjaxRequest())
return PartialView("_Foo", model);
return View("Foo", model);
}
}
Note: It's recommended to use WebAPI controllers to handle only json data. So if the user got there by typing the url the mvc controller will handle it and if you need to get the json data for that view you could call the webapi controller.
Use a separate controller or action method for AJAX and for Views. The View controller should match the URL. The Ajax controller should be the less "pretty" URL since it's behind the scenes.
You need to set up a routing definition in global.asax (MVC 3) or App_Start/RouteConfig.cs (MVC 4) to handle the parameters if you haven't already done that.
routes.MapRoute(
"MyRoute",
"MyUrlController/{action}/{para1}/{para2}",
new
{
action = "Index",
para1 = UrlParameter.Optional,
para2 = UrlParameter.Optional
}
);
Then in the View controller:
public ActionResult Index(string para1 = "Default Value", string para2 = "Default Value")
{
// ...Handle parameters...
return View("_MyView", viewModel);
}
Returning a View object type is the key. The History API URL doesn't get it's data from the same AJAX source controller which returns a PartialViewResult.

How to apply single page application functionality on parts of asp.NET MVC3 projects?

So I'm creating a asp.NET MVC3 application and want to apply single page application functionality to parts of the application. I think the easiest way to explain is with an example:
The app consists of an admin area and a public area and is built using ordinary link-structure. I want to convert the admin area to an single page application reusing view and models from the existing application. Is it possible to do this and in that case how?
You have to face two main problems, which makes the difference between SPA and standard application:
Links: In standard application, each link redirects you to a different page.
Forms: When a form is been submitted, a request is been issued with the HTTP method you've specified in the post (usually POST) and it contains in the payload the data the user has entered.
In order to solve that problems, you have to take action both in client-side and server-side.
For explaining propose, lets take the following code:
HomeController.cs:
public class HomeController : Controller {
public ActionResult Index() {
return View();
}
public ActionResult Contact() {
return View(new ContactUsViewModel());
}
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Contact(ContactUsViewModel model) {
if (ModelState.IsValid) {
/* Send mail / Save in DB etc. */
return Redirect("Index");
}
return View(model);
}
}
Index.cshtml:
<p>This is a simple page.</p>
<p>#Html.ActionLink("Click here to contact us", "Contact")
Client-Side:
We should fix up linking between pages, as well as forms submittions.
Links: You can wire up an event in JS (jQuery if you'd like) that'll observe for each link click in the areas you'd like to apply on SPA - then, instead of redirecting the user - you'll load the content via AJAX.
For instance, take a look at this sample:
$("a").click(function(e) {
e.preventDefault(); // Disable standard redirecting
var href = $(e.currentTarget).attr("href");
$.get(href, function(responseText) {
$("#main-content-wrapper").html(responseText);
});
});
Forms: Just like in the approch we've used for links, we can wire up an observer to the form submit event in JS and then transfer the data using AJAX.
For instance:
$("form").submit(function(e) {
e.preventDefault(); // Disable standard submittion
var data = $(e.currentTarget).serialize(); // Serializing the form data
var method = $(e.currentTarget).attr("method");
if (typeof (method) == "undefined") { method = "POST"; }
$.ajax({
method: $(e.currentTarget).attr("method"),
parameters: data,
statusCodes: {
404: function() { /* Handle it somehow */ }
403: function() { /* Handle it... */ }
200: function(response) {
/* Since we've done a form submittion, usurally if we're getting standard OK (200) status code - we've transffered a data - such as JSON data - indicating if the request success or we got errors etc. The code you're writing here depends on how your current application works. */
},
});
});
Server-Side:
Since you don't wish to break your current application logic - you have to still be able to use standard ASP.NET MVC methods - such as View(), Redirect() and so on.
In this case, I recommend to create your own custom base Controller class - which will override ASP.NET basic implementation.
For instance, this is a starting point:
public class MyController : System.Web.Mvc.Controller {
public override View(string viewName) {
if (Request.IsAjaxRequest()) {
return PartialView(viewName); // If this is an AJAX request, we must return a PartialView.
}
return base.View(viewName);
}
}
Few things you have to keep in mind:
You have to somehow distinguish between standard requests and AJAX requests - the way I've used with Request.IsAjaxRequest() is a great way to do so.
Many times when you're handling a form, In the form submittion action, after you finish with the form logic, you're using Redirect() to redirect the user to another page. As you may have guessed, you can't take this approch when developing SPA. However, I can think of few solutions for this problem:
You can create a status handler in the JS code so when redirecting is been issued by the server - you can load the content via AJAX / display a message and so on.
You can override Redirect() and add a specific logic to perform in case of redirection when the request was done by AJAX - for instance, you can request from ASP.NET to perform the action that you're going to be transfered into and then return its content etc.
You can decide that although its an SPA app - when a redirect was issued - you allows the server to perform this redirection.
As you can see - there're many approches you can take, and they depends on the way you've developed your site, how you wish it to work and what is the basic rules you're defining (e.g. "No redirection is permitted never - even after submitting a form", "After form submittion - always in case that the operation success - I'm displaying a message or performing other JS action. Because of that, I can override Redirect() and if this is an AJAX request I can return a JSON object." etc.)

Show validation messages on GET

We have a possibility that data loaded from a GET operation could be invalid for posting, and would like to be able to display the validation messages when the data is first loaded. The validation all takes place on server side using ValidationAttributes.
How can I force the validation summary to be displayed when the data is first loaded? I am guessing that I need to force errors into ModelState somehow, but I first need to get them out of the model class.
I ended up adding a validation method for the model class which adds errors to the ModelState. Then I created and added a custom ModelValidator and AssociatedValidatorProvider
for calling it during the normal validation that takes place during form binding. That way the controller actions that don't bind to the Model class directly can still have a call to the model's .Validate(ModelState) method to fake a validation. This approach works well for server-side-only validation.
UserInfo Model class:
private IEnumerable<RuleViolation> GetRuleViolations()
{
List<RuleViolation> violationList = new List<RuleViolation>();
if (String.IsNullOrWhiteSpace(FirstName))
violationList.Add(new RuleViolation("First Name is required.", FirstName"));
return violationList;
}
public void Validate(System.Web.Mvc.ModelStateDictionary ModelState)
{
foreach (RuleViolation violation in GetRuleViolations())
{
ModelState.AddModelError(violation.PropertyName, violation.ErrorMessage);
}
}
This is how it can be used directly from a controller action. In this action the Model class object is returned as part of the UserSearch model.
public ActionResult Search(UserSearch model)
{
if (this.ModelState.IsValid)
{
model.Search();
if (model.UserInfo != null )
{
model.UserInfo.Validate(ModelState);
}
}...
That is all I had to do for the particular use case I was working on. But I went ahead and completed the work to do "normal" validation on a postback: created a simple ModelValidator, with the Validate override looking like this. If you followed the above pattern in all of your Model classes you could probably reusue this for them, too.
public override IEnumerable<ModelValidationResult> Validate(object container)
{
var results = new List<ModelValidationResult>();
if (Metadata.Model != null)
{
UserInfoViewModel uinfo = Metadata.Model as UserInfoViewModel;
foreach (var violation in uinfo.GetRuleViolations())
{
results.Add(new ModelValidationResult
{
MemberName = violation.PropertyName,
Message = violation.ErrorMessage
});
}
}
return results;
}
Finally, extend AssociatedValidationProvider to return this ModelValidator and add it to the ModelValidationProviders collection in Application_Start. There is a writeup of this at http://dotnetslackers.com/articles/aspnet/Customizing-ASP-NET-MVC-2-Metadata-and-Validation.aspx#s2-validation
I don't know if understand what you need, but here is it...
run validation to display the validation summary when the form is loaded, using jquery
$(document).ready(function() {
$('#FormId').valid();
});

How to disable validation before calling UpdateModel in MVC3 Controller

I'm looking to enable "saving" of form data prior to submission.
I want users to be able to save form progress, even when the form is in an invalid state, and then come back to it at a later time.
Now, my only problem is that I want to be able to use UpdateModel method to update my model. However, as the form is potentially invalid or just partially complete, this will throw an error.
Is there a way to annotate the following method such that validation is ignored in the SAVE instance?
[HttpPost]
public ActionResult Save(Model values)
{
var model = new Model();
UpdateModel(model);
}
I want to save having to write a 1-1 mapping for the elements being saved - which is my fallback option, but isn't very maintainable.
Give TryUpdateModel(model) a try, should fit your needs.
This won't throw an exception, and it will update the model and then return false if there are validation errors.
If you care about the errors, you check the ModelState in the false instance.
Hence, you can use it as so to always save changes:
[HttpPost]
public ActionResult Save(Model values)
{
var model = new Model();
TryUpdateModel(model);
model.saveChanges();
}

Where to validate and test user input date, In the controller or the model?

Where to clean up/ validate/ verify the user input data? In the controller or the model?
In controller.
Look at it this way: Your form will post to a controller function with the form data in $_POST variable. You validate the data in that function of the controller and do some DB inserts or updates. Then you show the success message as a view or in case of error a fail message.
See the form validation tutorial in CodeIgniter's user guide here.
I'd go with the model so your validation can be reused. Models should handle the data and the controller should direct it to where it needs to go.
The code that make the validation must be in the model, but the call to this code must be in the controller.
Something like this:
class MyAwesomeUserModel {
public function isValid()
{
//some code to validate the user
}
}
class MyUserController {
public function myUserAction()
{
//some code to insert the input of the user in the model
if($userModel->isValid()){
//do nice things with the data and send some message/data to the view
} else {
//send 'nice' error messages to the view
}
}
}
This is just the way I use, may not be the best way, but it's the best fit in my application. And that's what matters, you should look for what best suits your application.

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