Let say I am rendering list of products with Add To Cart link / button next to each.
I also have a CartController with AddToCart Action that accept a parameter of Product type.
After product is added to cart user should stay on the same page (Product list) - not to be redirected to Cart or something.
I am rendering Cart summary partial view that should update itself.
So my question is about implementation of the Add To Cart link / button.
Should I use: Html.ActionLink(...)
or Html.BeginForm() and Submit button.
Maybe there is other ways...
How do I send Product info in each case?
Thanks
I suggest using a jQuery.post() request to your CartController.AddToCart. Make AddToCart a partial view. And then show a modal popup (div on top of your page) that shows that the product was added to the cart...then do a fade out!
Keep it simple.
Now keep in mind that some of your users won't be able to support jquery/javascript. So make the initial add to cart button post to an add to cart page (not partial page..full page)...which can return them to the original page. Then spot weld your jquery function on top of the add to cart button. This way you cover both worlds nicely.
Take a look at the concept of unobtrusive javascript/jquery.
The way I do it is to have a form for each add button (with maybe the quantity also), since you want your AddToCart action only receive POST actions anyway, that way you process all the add to cart logic and then redirect to your main catalog view (or something like that :)
Again I'd take into consideration what happens if the user doesn't have javascript. It's not very likely these days, but do you want to lose a sale just because someone accidently turned off javascript?
So what I'd do is create the somewhat typical AddToCart link (<a class="add" href="/Shop/AddToCart/5">). The AddToCart controller would then do it's stuff and redirect back to the product listing page (you might have to pass a parameter to specify which page to go back to).
So that's the first step to consider -- javascript turned off. Now you can think about how to do it with javascript.
Capture the click event ( $('a.add').click(...) ) and then you can do two things. One would be to call the URL (you can get it out of the event object) and then separately update the cart. You can also add a parameter to the URL so that it displays the cart partial view, doing something like (written from memory):
$('a.add').click(function(event) { $('#cart').load(event.target.attr('href') + '&showcart=1');
James
Related
I have an index page with items and a quantity select form.
The form works for create (a.k.a. first click). The problem is, if I click it again, it's just updating the cart instead of adding that quantity to the line_item. If this was my only problem I would be able to solve it myself.
The real problem is that I have another form that updates right before checkout. It looks like this:
I want this to be the master quantity control, so whatever goes in that form is what the quantity will be for update. But for the first images, I want that quantity to add to the quantity of the #line_item, so I can't just make a method that just adds the new and old quantities together, which is what I started doing until I realized I wouldn't be able to do that.
Do I need to make a new action in the controller?
What would be the work around for this?
Looking at your question
The problem is, if I click it again, it's just updating the cart instead of adding that quantity to the line_item
The problem is your submit button Add to Cart which takes it to the create action of your cart and hence creating a new item inside your cart
Do I need to make a new action in the controller?
My answer would be yes. You need to make a new action with post route request(to find that item) and then update its quantity inside that action.
What would be the work around for this?
If you look at your button or rather i should say form for creating a new item then it's the path or url part in your form which takes it to your method inside your controller. If you change its url then it will take it to your custom method.
Fix
All you need is some js magic to dynamically change the url or your form after a user has clicked on your Add to Cart button. Something like:
$(document).on("click","your_button_class",function(){
$(this).closest("your_form_class").attr("action","path_of_new_method");
});
You will also have to supply your items id by this form by adding a hidden field or something and then find that item inside controller method with that id to update its quantity.
Note: You need to call this js after your form is submitted and a new item is already created else it can trouble you.
I'm making the transition from webforms to MVC (I know, 3 years late) and I "get it" for the most part, but there's a few things I'd like advice and clarification on:
First off, what happens if you want to dynamically add inputs to a view? for example, in an old webform for generating invoices I had a button with a server-side click event handler that added an extra 5 invoice item rows. The stateful nature of webforms meant the server handled the POST event "safely" without altering the rest of the page.
In MVC I can't think how I'd do this without using client-side scripting (not a showstopper, but I would like to support clients that don't have scripting enabled).
The second problem relates to the invoices example. If my Model has a List, how should I be generating inputs for it?
I know data binding is a possible solution, but I dint like surrendering control.
Finally, back to the "stateful pages" concept - say I've got a Dashboard page that has a calendar on it (I wrote my own calendar Control class, the control itself is stateless, but can use the webform viewstate to store paging information) - how could a user page through the calendar months? Obviously POST is inappropriate, so it would have to be with GET with a querystring parameter - how can I do this in MVC? (don't say AJAX).
Thanks!
In MVC you design your actions to accommodate your needs. For example, if you wanted to be able to add 5 rows to an invoice NOT using client-side scripting, you'd probably have your GET action for the invoice generation take a nullable int parameter for the number of rows. Store the current number of rows in the view model for the page and generate a link on the page to your GET action that has the parameter value set to 5 more than the current value. The user clicks the link and the GET view generates the page with the requested number of rows.
Controller
[HttpGet]
public ActionResult Invoice( int? rows )
{
rows = rows ?? 5; // probably you'd pull the default from a configuration
...
viewModel.CurrentRows = rows;
return View( viewModel );
}
View
#Html.ActionLink( "Add 5 Lines", "invoice", new { rows = Model.CurrentRows + 5 }, new { #class = "add-rows" } )
You would probably also add some script to the page that intercepts the click handler and does the same thing via the script that your action would do so that in the general case the user doesn't have to do a round trip to the server.
<script type="text/javascript">
$(function() {
$('.add-rows').click( function() {
...add additional inputs to the invoice...
return false; // abort the request
});
});
</script>
Likewise for your calendar. The general idea is you put enough information in your view model to generate all the actions that you want to perform from your view. Construct the links or forms (yes you can have multiple forms!) in your view to do the action. Use parameters to communicate to the controller/action what needs to be done. In the rare case where you need to retain state between actions, say when performing a wizard that takes multiple actions, you can store the information in the session or use TempData (which uses the session).
For things like a calendar you'd need the current date and the current view type (month/day/year). From that you can construct an action that takes you to the next month/day/year. For a paged list you need the current page, the current sort column and direction, the number of items per page, and the number of pages. Using this information you can construct your paging links that call back to actions expecting those parameters which simply do the right thing for the parameters with which they are called.
Lastly, don't fear AJAX, embrace it. It's not always appropriate (you can't upload files with it, for example), but your users will appreciate an AJAX-enabled interface.
In MVC you can store application state in various ways. In your controller you have direct access to the Session object and you can also store state to the database.
your view can contain basic control flow logic, so, if your model has a list you can iterate over it in the view and, for example, render an input control for each item in the list. you could also set a variable in a model to be the maximum number of rows on the viewpage and then render a row in a table for the number specified by the model.
paging is basically the same thing. you can create a partial view (user control in the webform world) that shows page numbers as links, where each link calls an action that fetches the data for that page of results.
i'm not sure what your beef is with ajax or javascript
I am building a search form for my web application using MVC3. My form is basically divided in two sections.
1st Section has 3 search criteria. First Name, Last Name and Zip code and beneath that section there is a "Search" button which I can click and it should do a client side validation and give me an error message if any of the fields are blank.
2nd section on the same page has just one textbox - to search by "Quote Number". So that section has one textbox to enter quote number and beneath there is another button called "Search". When I click on this search button it should only validate that the Quote Number field is not empty.
I have a viewmodel which has all 4 properties (FName,LName,Zip,Quote Number) and I am binding that on the page. Both the button will post back the page (I know that there is a way to identify which button was clicked on postback). The problem I am facing is on postback everything is posting back and if I use datannotations to do RequiredField check, it does validation on all the 4 fields but I should check for which button is clicked and based on that only fire validation on either 3 fields or only on 1 fields. How do I achieve this functionality? I hope I clearly explained the issue.
Thanks
Since this is MVC, don't think of these as postbacks, think of them as submits. As they are searching by different criteria, they should really be two different forms submitting to two different actions. As they are separate actions, each can have it's own view with it's own ViewModel and validation. Then to combine them into one physical page to present to the user just use partial rendering to put them both into the same view.
Basically the view you present to the user would have something like:
#{
Html.RenderAction("SearchByName");
}
<!-- maybe some markup to visually separate them -->
#{
Html.RenderAction("SearchByQuote");
}
Also gives you the added benefit of having each action be responsible for a single task and you don't have to put in code to figure out which button was clicked, etc.
And just in case you think to yourself "Hey, since both are search, just with different number of parameters, can't I overload the Search action?" No.
Kevin,
Change your page so that you have two different forms, one for each search type. When you click submit in one form, only that form's child fields will be validated.
Then, as R0MANARMY suggested, have two separate actions, one for each search form.
counsellorben
I have a asp.net mvc page which renders a record from a database, it uses RenderPartial to call another view which renders an editable list of items related to that record.
My problem is I want a since save / submit button which not only saves changes made for that record but also changes made in the RenderPartial part... I have created a method accepting POST in the RenderPartials controller but it doesn't get called? Any ideas? Or am I using RenderPartial wrongly? I did it this way so that I have a controller that handles the subset of data
Update:
I don't think I've been clear enough:
Imagine a situation where you have a page that is filled with information from lots of different tables in a database... for example imagine you have a record of a person, and then you have all the links they have to Organisations that you want to list on the page, so the page contains:
Individual Name, Email, etc...
AND
Organisation Link 1
Organisation Link 2, etc... from a link table
Because of the amount of data I want to render of the page, I figured using different controllers to render each part would make sense.. but then when saving the data do I have to use just one controller method or can I call one controller to another... I only have one form and one 'save' button for the whole page
I hope this is clearer?
You don't need to have a specific controller for each controller, although I suspect you meant to say "I have created a method accepting POST in the RenderPartial's action ..."?
When you accept the default html helper commands, it can sometimes get confusing which action will be called. For a particular web page, the tag will determine where to POST values. So the action called will be dependent on the controller/action you specify in your Html.BeginForm call.
For example, here's a form we use from an ascx page:
<% using (Html.BeginForm("InvoiceDetail" //Action
, "CompanyInvoice" //Controller
, FormMethod.Post
, new { #id = "InvoiceForm", #autocomplete = "off" }))
{%>
A form can post to any action, in any controller. Not that you'd want to, but it's quite flexible. You can also have multiple forms in a single web page now, which is great for complex forms.
In my MVC application for booking accommodation I have the following:
Action to display the selected room with input-forms for extra info GET:"Details"
This view has multiple forms on it, each posting to a different action.
Examples:
Action to update the number of guests POST:"UpdateGuests"
Action to select start date POST:"SelectStartDate"
Action to add breakfast POST:"AddBreakfast"
Action to delete room POST:"RemoveProductFromCart"
Action to proceed to next step POST:"Proceed"
Most of these actions will redirect back to the GET:"Details" view so the user can perform another action if required, in the case of the proceed, this will redirect to the next view OR if there is some reason they cannot proceed it will display the validation message as to why on the "Details" view.
I'm not sure of the best way to deal with validation, here's some options I've thought of.
use TempData[] to store validation messages and REDIRECT to "Details" view where we add any TempData errors so the ModelState.
in the POST:"xxxxxx" Action populate the ModelState and RENDER the "Details"
This is not a high volume site so TempData is an option.
Any ideas gratefully welcomed.
Edit:
Additional info:
I'm using DataAnnotations for validation rules in some places.
adding Ajax as progressive enhancement is planned, but it should work without.
I think that your second option is the best : each post actions will do the required validations, populate the ModelState with the error messages and every post will return the same view, rebuilt using your model.
Another option, a little bit harder but giving a much better user experience is to do some actions (like update number of people, select start date, add breakfast) using an ajax call. That way, you can return only the little bit of informations required by this action, refresh only that part of the screen and add some error messages if needed.
I hope it will help.
Have you taken a look at how nerd Dinner does validation? I've used this approach with forms that contain several Partial Views and it works great.
You can even modify to validate using jQuery on the fly if that's what you want to do.