How do I submit a form within a partial view? - asp.net-mvc

I am asking this question to make sure myself that I understood the subject.
"The only way to have a submit button inside a partial view is using Ajax techniques to submit the form"

Well, technically you could do a normal postback from a partial view. But that would tend to defeat the point of a partial:
the entire page would have to be re-loaded, which means the result of the partial-view postback would need to be a complete page.
the partial view's modularity suffers, because the result of its postback falls out of the partial view's scope (ie, the partial view needs to know about the entire current page).
So, it's an irregular thing to do a non-AJAX postback from a partial view. But there are scenarios where it would be useful/appropriate. Consider for example a "login" partial: you may want to post the credentials back to a specific controller/action, and have that action redirect back to the current page. In that case you could reasonably use a non-AJAX form.

The only way to have a submit button inside a partial view is using Ajax techniques to submit the form
You didn't say where you got the quote from, but this isn't true.
You submit a form from a partial view in exactly the same way you submit a form within a main view. You can do this using custom fields or by making your partial view strongly typed. Where are you getting hung up?

Related

How do I implement a logon HTML form as part of my master layout?

I have a requirement to include logon fields in my right column of a 3 column layout, with the body view being the centre. Right now I simply have Logon actions in my home controller, but IN haven't given this much work yet and am running into difficulties. I use a partial view for the HTML form with login fields, but I want to move the logon actions into my Account controller. However, my quandary is how to. so to say, return a partial view from an action method, e.g. for a bad logon message.
For that purpose, Html.RenderAction is used. Simple way to inject output of other menu, logon, etc. actions into generated html
Do you use AJAX or you submit the form back?
I would suggest using AJAX to send the form data. If the login is unsuccessful you can return some string or whatever message you like (you can also return the partial view), if it is successful you can authenticate the user and redirect to home page.

ASP.NET MVC 2 Submitting from partials in different views

If I have a partial that is used in multiple views that submits to its own dedicated action, then how do I know which view it has come from so I can go back to that view?
I think it's answered here: Retrieve the current view name in ASP.NET MVC?
Just to clarify - How do you mean 'so you can go back to that view'
If you use ajax forms ie Ajax.BeginForm for each of those partial views, they will all automatically handle their own psots to the url (hence controller) and can live peacefully in the parent view no matter which view it is.
if model validation happens, then you will see it in those partial views and modelstate will repopulate the posted values into the model for the user to 'fix'

ASP.NET MVC Catching 'Save' POST with RenderPartial

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.

ASP .NET MVC: Html.Radiobutton onclick -- set ViewData[""]

I'm new to ASP .NET MVC and to web programming in general.
I'm wondering if there is a way to set ViewData variables when a radiobutton is selected -- but before the page is submitted.
Maybe I'm barking up the wrong tree but what I'm trying to do is create a form where new fields are added based on which radio button is selected. So what I want to do is when a radiobutton is clicked it sets a ViewData variable and based on that ViewData variable a different partial view loads the appropriate fields below the current field.
I imagine there must be someway of doing a onclick="some C# function that sets ViewData(args)"
Thanks
There are a couple of ways you could go about this.
1) You could have an Ajax form where through Javascript you post the form back and check to see if it's an Ajax Request, there by returning a partial view to a div that you specify.
2) Post the form as is and check server-side to see if the radio button was clicked, and thus redisplay the form with the new options visible.
If you take the first approach it would be easy enough to fall through to the second one for those without Javascript enabled.
There aren't really "onclick" events as I'm assuming you are used to from Webforms, you would basically have to roll your own Javascript to handle such things. Once you do a few, I think you'll find it's really not too bad, with the benefit that you'll have more control over what you're doing and through that gain a better understanding of the larger picture.
ViewData only exists, and only exists server-side, for the lifetime of the request. So, once the page is rendered the object no longer exists.
Some alternate approaches you can take:
1 - Use client-side Javascript to add a form and inputs as necessary. More info here:
ASP.NET MVC & JQuery Dynamic Form Content
2 - Pre-render the new form, but hide it via CSS, and unhide it when the appropriate radio button is clicked. More info here:
expand collapse html field Firefox
3 - Use AJAX to render the new form when the appropriate radio button is clicked. More info here:
http://www.asp.net/learn/mvc/tutorial-32-cs.aspx

POST method called on MVC UserControls as well as their parent views

Rewritten: My original post seemed to be misunderstood. I have since reported it as a bug with the following description. My original post for this question can be found below the second <HR>.
I have a major issue with POST in a user control.
I have a UserControl which has a controller containing two ActionMethods called 'ContactForm'. The second has ActionVerb.POST on it to respond to the post-back. The user control is primarily used via AJAX - but that actually is irrelevant here. Obviously these action methods render a partial view.
I have a main page containing an additional html form for 'EnterContest'. Again - its controller has two ActionMethods called 'EnterContest', one of which responds to ActionVerb.POST. This view contains the 'ContactForm' in a side bar which is rendered with :
<% Html.RenderAction("ContactUsForm", "Company", new { commentsBoxHeader = "Questions" }); %>
The problem occurs when posting back the 'EnterContest' Form (the main form on the view).
The POST request from Fiddler contains just this query string (obviously not containing any of the POST data from the contact us form because thats a completely separate HTTP ACTION).
contestId=ND09&email=fred&btnEnterContest=Submit
(yes, this looks like a GET but thats
what Fiddler shows for a POST too)
First - (as expected) - the 'EnterContest(FormCollection data) method is called in the main controller. This processes the form submission to enter the contest - calls the webservice etc..
Second - (NOT expected) - The POST method of the 'ContactForm' controller is called. This immediately crashes because it is missing expected parameters - and we don't want it called anyway. This happens during the same Http request.
If I take a look at the stack trace - it is being called from the dynamically generated aspx page - originating at the Html.RenderAction line of code shown above. So obviously what is happening is the code that is looking to partially render the 'ContactUs' action method looks at the Request and sees there is a method to handle POST so it routes it there - which is VERY BAD. Its probably somewhere around this method in the framework :
System.Web.Mvc.dll!System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod
This behavior is VERY confusing and really breaks what seemed to be a simple page. I'm pretty sure it is a bug - because I cannot see an elegant work around without some really clumsy checking in my controller. I think RenderAction is in futures - but I don't know if the issue is present there or in the main framework.
Just to clarify what is NOT happening :
any clever jQuery
more than one HTTP request (verified in Fiddler)
nested forms
Thanks
Original post
I am using the RenderAction Html extension in ASP.NET MVC.
I came across something unexpected, but which is making more sense as I think about it.
Lets say I have a view containing a 'RenderAction' method to generate the contact for a part of the page.
<% Html.RenderAction("ContactUsForm", "Company",
new { commentsBoxHeader = "Questions" }); %>
In this case the partial view it generates creates an ajax form which posts back via <%= Html.BeginAjaxForm() %>.
So of course I need an actionresult to handle the AJAX postback.
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult ContactUsForm(FormCollection formdata)
Now the problem occurs when the parent view containing this partial render action has a normal (non-ajax) form with a POST action. What happens is that the POST method for the ContactUsForm action is call in addition to the POST action for the main view. Inside this action the formdata property contains all the properties for the parent view - so ContactUsForm dies with a null reference or something like that.
I've come up with 3 possible solutions :
1) create a different action name for the post back for any user controls on the page. This has the disadvantage that you have to post back to a different function than created the partial view. Often this can be more cumbersome but this is what i'm doing right now.
2) check in every POST method (you'd have to remember to run this check in every user control's POST action method) to see if the form data is intended for that form it, and if not return a default view.
[AcceptVerbs(HttpVerbs.Post)]
public ActionResultContactUsForm(FormCollection formData)
{
if (formData["btnSubmitContactUsForm"] == null) {
// "This form is not for us!";
// figure out how (if is possible) to return the get default view here
// and call it with the right arguments
}
}
3) report it as a bug.
What should I be doing here? I'm leaning towards thinking of this as a bug
Edit: One very important thing I need to stress more is that BOTH POST methods are called - so its not just somethig like a nested form.
Edit 2: In Fiddler I see only one request. The problem is when it tries to render the ContactUsForm after having already handled the POST for my main page it hits the 'POST' method for 'ContactUsForm' instead of the non-post handler.
EDIT2: I just noticed that you are using RenderAction instead of RenderPartial. I suspect what is happening is that it is using the RequestContext of the posted form to choose which ContactUsForm method to choose when the RenderAction is invoked. This is arguably correct behavior since the action is being invoked from a postback, just not the one you intended. I would approach this in a completely different manner. Have the partial generated by a ViewUserControl and include it on the page using RenderPartial instead. Remove the GET ContactUsForm method and only have the POST version. That is, the form itself is generated as a ViewUserControl with markup predetermined or dynamically generated via parameters passed via ViewData. The form response is handled via the controller action.
EDIT: Since you indicate that nesting is not the issue, is it possible that you are using javascript (say jQuery) to trigger the submit and your selector is too broad. If, for example, you had code like the following, that would account for the behavior you are seeing.
$(document).ready( function() {
$('#mybutton').click( function() {
$('form').submit();
});
});
Original answer: (left for context)
It sounds like you have nested forms in your view. Try moving the RenderAction outside the form in the parent view and see if that fixes your problem. My feeling about forms in MVC views is that they should be compact and only cover the markup that contains the actual inputs. This is a change from WebForms where you typically wrap all of your mark up within the form. Use CSS to control layout if you need to have the form elements appear to be intermixed.
This is actually a confirmed bug both in ASP.NET MVC 1.0 with MVC Features library and in ASP.NET MVC 2.0.
RenderAction behaves incorrectly when the request is POST.
I have submitted the bug in ASP.NET Issue Tracker on Codeplex, please vote for it :)
http://aspnet.codeplex.com/WorkItem/View.aspx?WorkItemId=5847

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