I need to send parameters with values in a BeginForm html.
Example:
# using (Html.BeginForm ("Create", "IncomeDeclaration", new {declarationAmount = document.getElementById ("element"). value}))
This value I can not get from the Model, as it is not found in the model.
I've tried several ways and nothing worked. If you could change the content of a ViewBag that'd be great.
I appreciate your support.
You can't mix and match Javascript (document.getElementById ("element")) with the C# form declaration. If you want a value submitted with the form, you should add a relevant form element inside the form declaration. If you don't want a regular form element (eg. a textbox), you can use a "hidden" input field. If you want, you can dynamically populate the hidden field using javascript.
Related
I have an dot net 5.0 mvc page which takes a model object (ClassFoo) which when constructed generates an instance of (classBar). ClassBar has various properties (FieldA, FieldB, FieldC) all are strings.
The Views content is all in a form and the form's input fields are all from ClassFoo.ClassBar's various properties. Initially, when the page is accessed, all form input values are empty. However when I put data into them and then submit the form, the form values are still there when the page loads. However I don't understand why this is because I'm explicitly creating a new model during the controller operation but I am not actually populating the Model.ClassBar with the content from the post before I return model to the View for generation.
What I would expect is that all of the form fields would be empty however that is not the case. I know if asp.net the form values are stored and restored automatically but I didn't think that happened in mvc.
After looking into ModelState recommended by Nick Albrech in the comments I reviewed the hint associated w/ the HtmlHelper.TextBoxFor() which states the following:
... Adds a "value" attribute to the element containing the first non-null value found in: the ActionContext.ModelState entry with full name, or the expression evaluated against ViewDataDictionary.Model. See [IHtmlHelper.NameFor] for more information about a "full name".
So effectively what's happening is similar to what I thought asp.net mvc wasn't doing in that it populates the ModelState from a get/post request with the name and values of the form being submitted. Then based on the use of these helper functions (and also asp-for attributes used in razor views views), it either provides values from the saved model state form values OR the model passed to the view. Note: this does not seem to work if you set the value of an input element = #Model.[someProperty]
The take away from this is that you do not necessarily need to update your model object with content from the previous form submit in order to have the page populate the form contents back to the screen. Allow asp.net mvc to do the manual tasks by making use of these razor helpers.
Shoutout to Nick for the assist on this one. A solid member of the stackOverflow community.
When you want to create a DateTime picker control with JQWidgets, you must define a div element and then call a function like this using Javascript:
$("#MyDivElementId").jqxDateTimeInput().
The problem is: I'm not able to figure out how I can use Model Binding of Asp.Net MVC with this syntax. I mean, the Model Binding feature will try to match key-value pair received from input controls in the form element and obviously, div element are not input control.
I found somebody who already resolved this problem using hidden field set with values of matching div JQWidgets element before submitting form but I don't like this solution; it's not natural and I must write to much code for a thing that should be simpler in my view.
Does anybody have more elegant solution?
If you set the "name" attribute of the DIV tag, the value from the DateTimeInput's Input tag would be submitted.
First of all when you submit id is not submited and i just opened that plugin demo. when you add code $("#MyDivElementId").jqxDateTimeInput(). it will create textarea with name MyDivElementId and when you submit then you will have the same value on server side. Other issue can be with date format since they would be probably different on client side and server side.
try to add input parameter for controller "DateTime MyDivElementId" and check if its null or not.
I am using Rails 3.1 to build a web form which, among other fields, contains a table whose cells can be edited. I require to save the text of edited cell in a database.
I am thinking of using HTML5 attribute 'contenteditable'. I can use the value of innerHTML of the cell . How can I pass this value to Rails controller (from the view)? Is it possible to use params to pass the data? Any suggestions?
HTML containers marked as contenteditable won't automatically be passed along to the server with a form submission, so you'll likely have to use javascript to pull the content out of those containers and pass them along in some fashion.
One strategy would be to add a handler to the form that fires before submit, which iterates over contenteditable containers and injects hidden form elements. The below example uses jQuery, but you could probably replicate the thought process without.
var form = $('#my_form');
var element;
$('[contenteditable=true]').each(function(){
element = $(this);
form.append($('<input/>', {
type:'hidden',
name:element.attr('id'),
value:element.html()
}));
});
I have uploaded my code to pastebin, this is the link:
http://pastebin.com/wBu9PP2x
When i submit a form, the Lists that i use are not bound to my ViewModel.
But when i send the ViewModel to the view, it renders fine using EditorFor. I have read that when using EditorTemplates, it is supposed to name the List appropriately so that they are bound to the ViewModel automatically upon postback.
The HTML output can be seen here:
http://pastebin.com/5KeyNXWC
Notice that the ViewModel derives from ShowQuestionViewModel, which contains some strings. These strings get bound perfectly.
This is the tutorial i have been following:
http://jarrettmeyer.com/post/2995732471/nested-collection-models-in-asp-net-mvc-3
In the tutorial, the MVC framework knows how to bind lists inside of a ViewModel.
Here are some debugger outputs:
Controller takes ShowQuestionViewModel as parameter:
http://imageshack.us/photo/my-images/803/debug.jpg
Controller takes FormCollection as parameter:
http://imageshack.us/photo/my-images/542/formcollection.png
Different Controller that takes a List and FormCollection as parameter:
http://imageshack.us/photo/my-images/685/listtest.png
Dont give up on me guys!!
Thanks!
Solution
I have found this solutin myself. I forgot to use Properties for the rows and columns list in the ShowMatrixQuestionViewModel. Also, the ActionController wont bind without TryUpdateModel() so thanks to #Adam Tuliper as well as the rest.
Since you mentioned lists are you sure your model Upon postback contains all of the expected items? Also remembe the HTML helpers will use modelstate to bind data from as well if you are showing data after a post and not redirecting.
I am using javascript to append user selections to a list. When user is done , which is the best way to go:
1: create index for the list and submit as model in a form to the controller?
2: create hidden element and use javascript to append values and submit as actionlink? (not sure how to tell actionlink the value here)
3: wrap form block around the hidden element only and submit string as model?
other?
I think the easiest way is to put some form of your list to the hidden field (type=hidden) and it will be automatically submitted with form and accessible on server under the name you gave it. So main reasoning here is the way you going to process these data on the server side.
First of all, Scott Hanselman has a good post about model binding to arrays, collections, etc.
In my opinion you shouldn't use second way because this will be a vulnerability ( description of CSRF).
In order to use collections binding you'll need to wrap a form around a list and submit it (note, this form will submit only selected values in this list but you may select them all before submit) or to create a map of values and submit it via javascript (for jQuery - $.post(url, data, callback)) or to add all pairs of name&value to some hidden element of a form and submit it.