Using HTML forms in ASP.NET MVC? - asp.net-mvc

It seems like everything I look up on this subject has either changed since the release or is wildly different from eachother.
I just want to create a simple form in my view.
Should I be using the Html.BeginForm()/TextBox()/EndForm() methods or should I be using a plain-jane HTML form? Which is preferred?
This is what I have so far:
<%=Html.BeginForm("Create", "Product", FormMethod.Post); %>
<%=Html.TextBox("productTextBox", "Enter a shoe name"); %>
<input type="submit" name="createButton" value="Create Me!" />
<%=Html.EndForm(); %>
What is the "correct" way to create a simple form with a button and textbox in ASP.NET MVC and allow me to submit the data in the form to the /Product/Create action?
How do I then access the form data from within that method? Some people seem to use a "FormCollection" and others just do a Request.Form method. Which way should I use?
Can someone enlighten me?

The Form helpers are the recommended way because it allows you to provide a controller, action and other route data and the URL is auto-generated based on your routes (in Global.asax). The advantage is, if you decide to change your routes, you don't have to update every URL in your site.
The only reason I'd use an actual "<form>" tag was if I needed extra control over the markup that I couldn't get from Html.Form (I can't think of an example right now). Even if you choose to do that, you should use the "Url.Action" helper to get a URL from routing data. For example:
<form action="<%= Url.Action("Create") %>">
As for your second question, I'd suggest using the Model Binder. Check out ScottGu's Blog for some details on this.

Have a look at Link.
It's German text but the code should be understandable.

Have you looked at this:
http://weblogs.asp.net/scottgu/archive/2009/03/10/free-asp-net-mvc-ebook-tutorial.aspx
It's from the horse's mouth, and is up-to-date with the final release.

Related

Rails - Don't want to create a database with only one field, but don't know any other methods

So I'm trying to have an "address" input field on one of my view page, and i want to use that "address" as one of my parameters in my API call.
I am not sure if I should create a whole new controller/model just for this one address field, and I am sure there are definitely better ways to do this.
The idea came from Postmates Website, where on the homepage you can enter your address and Postmates will give you a list of available delivery services. I am looking for something similar to this.
Thanks in advance.
Create a form who's method points to one of your controller actions and then use the data from the form in that action.
So:
<form action="route/that/handles/delivery/address" method="get">
<input name="address">
<input type="submit">
</form>
Then in your controller action:
def handle_address
params[:address] // do stuff with this
end
Why do you need just one field on the table?
I agree it might be better to just send and update the parameter you want to change by modifying the controller instead.

Direct BeginUmbracoForm action to another page

I am trying to set up a global search box that posts to a search page in umbraco 7. This template uses a shared partial containing Html.BeginUmbracoForm() that points to a SurfaceController.
Since this is a global control, I want the form to be posted to the /search page instead of the current page. BeginUmbracoForm only seems to be able to post to the current page unless I'm mistaken.
I want something like RedirectToUmbracoPage(id), but clears this post values on redirect.
Is there a way to get an ActionResult like CurrentUmbracoPage which keeps the post values?
I would not try using surfacecontrollers for that purpose. Surfacecontrollers are auto routed. They are created to (e.g.) make #Html.Action(...) work on every umbraco page. Including postbacks on these actions or macros.
If you only need a "redirect" to the /search page, you don't need a surface controller. A simple partial will do the job.
<form action="/search" method="get">
Search <input type="search" name="q" />
</form>
Of course you can replace the url using some Umbraco logic like #Umbraco.TypedContentSingleAtXPath("//Search") or other Umbraco magic.
In the umbraco documentation project is an example where Html.Action is used.

What are the benefits, if i use rails view form template?

Example, i made a form like this
<form name="register" method="post" enctype="multipart/form-data">
<p><h3>User check</h3></p>
<p>admin ID: <input type="text" name="userid"></p>
<p>admin Pass: <input type="password" name="password"></p>
<input type="submit" name="apply" value="Submit"></p>
<p> </p>
</form>
and my manager wants to change this form to rails form template like this,
<%= form_for(:model) do |form| %>
<p>
<%=form.label :input%>
<%=form.text_field :input, :placeholder => 'Enter text here...'%>
</p>
<%end%>
My question is, it works fine with html based front code. Why do i have to change this to rails code? I just want to keep my front-end code...I don't know why i have to change this :(. Also, I'm new on Ruby on Rails. That is the main reason. I dont' want to change the existing code, if it is working.
I really hate this job. I have to translate all the attributes to the rails code and that makes me really exhausted :(
Form builders are here to help
Form helpers are supposed to make your life simpler. They are quicker to write than their pure html alternative, provided you don't write pure html first.
They also provide a lot of easy implementations for difficult integration pieces, like :
displaying a date selection select group
mirroring the fact that a check box has been unchecked in POST params
automatically adding multipart param on form if you add a file input (not actually difficult to achieve, but easy to forget)
... and many more
Further development
All of this is about comfort, and you may think you could avoid it if you already have a perfectly working pure html implementation.
But what happen if someone later has to add a date select input in your form ? She will have to use the rails helper, since it saves a lot of time in controller part to set date in database. But she won't be able to leverage form builder, since you haven't used it.
Now, she has to choose between using a non builderdate_select tag mixed in pure html or ... to rewrite your form completely. As you may realize, mixing different styles is generally considered ugly, and we don't like ugly in ruby.
Security
Form tag helpers also provide an important security measure : CSRF protection. Every time you use a rails helper to create a <form> tag, it automatically adds an hidden input containing a secret key. That key has to be posted with form data to prove request originated from current website.
If you use plain html forms, you won't have this security. You could of course add the token manually using the correct method, but this would again be more time wasting than simply using form helpers.
Bottom line
The main problem is that you write pure html before using rails helpers - that is what is wasting time.
Some benefits of using Rails form helpers are:
Consistent naming of input elements names and ids
i18n support for labels
generated URL with form_for is less error prone
Better handling of checkboxes
Nice helpers like options_for_select
Less typing
That last ones might be my favourite: less typing.

Structuring complex web forms in ASP.NET MVC

What is a good approach in ASP.NET MVC for implementing a complex form where sections of the form are shown and hidden based on a user's inputs?
My background is in Webforms. I am frequently asked to build forms where a user selects an option from a dropdown list, triggering a handful of new fields to appear. A different selection might cause a different set of fields to appear.
In the past, I would handle this scenario via an UpdatePanel and a wrapper Panel around the fields that I want to show or hide. Validation is automatically disabled when the fields are hidden.
Going forward, I'd like to make use of MVC's attribute-based model validation, but is it possible to make the validation conditional on the values of other properties?
Also, how can I handle the toggling of blocks of form fields? I know how to do it manually in jQuery, but I'm hoping there's an approach that ties in with validation and server-side code.
I am liking MVC much better overall, but I haven't figured out how to handle this type of scenario very well. Likely I just need to shift my thinking to fit better with the MVC approach.
Josh,
The first thing I's suggest is to make sure you use ViewModels for the pages that are mode complicated. A ViewModel is basically a Model you create for a specific View; for example, a ViewModel could be a composition of other classes.
As for dynamically changing the fields on your View, the best way is to use jQuery (or any other javascript library) to do it.
I also migrated from a web form environment and I know is difficult to change gears at the begining, but trust me, doing a simple jQuery even handler is much simpler than having to put in place a control panel and then the event handlers.
Not to mention that is much more efficient; update panels are after all making partial posts to the page, sometimes, with jQuery you don't even need to do that.
After a few projects with MVC, I actually now find it time consuming to go and do the Update Panels on web forms ;)
Hope this helps,
-Covo
I know this might not be the answer you're looking for, but I personally don't think complex forms are very user friendly in the first place and I always try to split them up into simpler forms where possible, or to simplify the form. I've come across many forms in websites where there are a raft of "fields" where there should really be a few questions for the user to answer. Simple stuff which gets to the point of what they want to achieve rather than the field values, along with a lot of application specific knowledge needed to set those fields to the right values.
If you still want to go ahead with a complex form, then as the other answers have already stated there are facilities provided by MVC to do that, but there isn't any set way. So, it's down to you to figure out what will work best for your users.
Traditional asp.net webforms did alot of "magic" for you whereas you have to be aware of the work that goes into creating the "magic" in asp.net MVC. The benefit is that with MVC you have more control over what is happening which can also enhance performance.
In asp.net webforms an UpdatePanel is used for ajax calls. If you need to got to the server asynchronously(without doing a full post back) then use ajax via JQuery. See below for example:
$.ajax({
type: "get",
url: "/YourController/YourAction",
success: function (obj) {
//any logic you want to do upon success
}
});
The above example will do an ajax HTTP GET call to /YourController/YourAction.
In order to handle "toggling of blocks", if you don't need to go to the server for data and you simply want to do it on the client, then use simple jquery. JQuery has a function for toggling items.
http://api.jquery.com/toggle-event/
Because of the way MVC works in contrast to Webforms you're stuck with the responsibility of really thinking about what happens on the client and what happens on the server separately as not a lot of meta-data is being passed back to give us that happy Webforms feeling.
However, there is a notion when using the built-in AJAX libraries when you render a form that you can have it auto do an update once it is posted. In a sense, it's saving you the JavaScript/JQuery because it "auto-wires" it up similar-ish to a Panel. In this way you could potentially look at progressively rendering your complex forms from the server as each section is edited, etc.
See MSDN: http://msdn.microsoft.com/en-us/library/system.web.mvc.ajax.ajaxoptions.updatetargetid.aspx
The relevant code example to give you an idea (unfortunately, it's not in the more readable Razor syntax):
The relevant line is the Ajax.BeginForm where the form tag is rendered. Once the form is posted, the MS AJAX library will auto update the element specified in "UpdateTargetId" specified in the form's AjaxOptions. In this case, the response will be placed into the SPAN element "textEntered" upon reply from the server. Here, you could progressively render more content to the user to fill out, perhaps another form, etc.
<h2><%= Html.Encode(ViewData["Message"]) %></h2>
<p>
Page Rendered: <%= DateTime.Now.ToLongTimeString() %>
</p>
<span id="status">No Status</span>
<br />
<%= Ajax.ActionLink("Update Status", "GetStatus", new AjaxOptions{UpdateTargetId="status" }) %>
<br /><br />
<% using(Ajax.BeginForm("UpdateForm", new AjaxOptions{UpdateTargetId="textEntered"})) { %>
<%= Html.TextBox("textBox1","Enter text")%>
<input type="submit" value="Submit"/><br />
<span id="textEntered">Nothing Entered</span>
<% } %>

Building pagination in MVC: Is there anyway to get something like an Html.HyperLinkFor

What I mean by that is a type element that will have a label based on a value in my viewModel and also be able to submit that value back up to the viewModel so it can grab new results based on Current Page and Page Size. This is for creating a gridview in MVC that supports pagination.
None of the examples I've seen of MVC so far have had anything resembling a gridview. It's important that I create my own paging and not use any built in paging mechanisms or third party controls or html helpers or the like
I'd go with ActionLink. To build Urls you can either use Url.Action or Html.BuildUrlFromExpression(c => c.conTrollerAction)
If you use T4MVC, you will get some nice helpers that do exactly what you are looking for.
Something along the lines of:
<a href="<%: Url.Action(MVC.MyController.MyAction(Model.ActionMethodParam1, Model.ActionMethodParam2)) %>">
You can also use the Html.ActionLink helper:
<%: Html.ActionLink("Link Name", MVC.MyController.MyAction(Model.ActionMethodParam1, Model.ActionMethodParam2)) %>
T4MVC is a great little library that I use in every MVC app.

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