I am using the MS shipped client side validation in asp.net mvc 2. The model in question has one property called "FirstName". Our client side developer really like to have camel-case in the elements id, so instead of using the normal html helper Html.TextBoxFor(m => m.FirstName), we wrote out the html input view instead like: <input type="text" id="firstName" name="firstName" />. The model binder can bind correctly and get the right valud ( I guess it was not case sensitive, which is a good thing). However, when we turn on client side valuation and issue a Html.ValidateFor(m => m.FirstName) at the end, it still generates the Pascal-case format of the property (which is expected).
I look into the mvc 2 source code reveils that ValidateFor() calls ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData) which in turn uses MemberExpression to get the property name (which is pascal case). I am wondering if there is way around this? The ultimate goal is to have camel-case ID is the elements of the html and still have both client and server side validation works.
Any help is appreciated.
My $0.02: Pick a casing and make the view model match the page. Both C# and JS are case-sensitive, and attempting to mix cases won't end well. One of you is going to have to change case. You could probably work around this specific issue, but it won't be the end of your problems.
Related
Let's say I want to build a web app which would use templates in the form similar to the following:
<h1>
{ status_text[step] }
</h1>
<progress max="10" value="{ value[step] }">
</progress>
In other words, let's say that I have lists value[] and status_text[], change only the variable step over time and want the form to reflect these changes in the real-time (ideally, even without sending a notification from the code that changes step, so that I can use current_time instead of some artificial step). What technology should I use to implement such behaviour in the most elegant way? (for the main language, I'd prefer using Python but JS/PHP would also work if there's no Python-related solution)
Thanks in advance for any advice.
These kinds of task are always accomplished in the client side, In other words in JavaScript.
No matter you use PHP or Python for your backend logic, you need JavaScript to do that.
That said, if you want to use pure JavaScript or a library like jQuery, you will have to trigger an event on every change of the progress and update the value of the h1 Element. I don't think this is the best solution for you.
So I suggest you using AngularJs. it's one of the leading web development technologies. AngularJs data binding allows you to accomplish this very easily. No need to trigger events or any extra work. if you're interested in AngularJs, here is a link to get started.
I've just been reading the article on MSDN about remote validation. This is great, but it only shows validating a specific property value.
Is there a way I can pass other values from my model into the validation for a particular property? For example, let's say that a user wants to cancel a number of items off an order - they should be prevented from entering a figure greater than the original order amount.
Thanks
No, you can't.
Brad Wilson:
At this time, only property level
validators can emit client-side
validation (as that lines up much
better with the idea of input
validation in the form of the
browser... there is no "model" to
speak of, from the browser's point of
view).
Stuart Leeks:
I don't believe you can hook up client
validation with IValidatableObject
Well, i am nit sure if you mean this, but you can use AdditionalFields with your RemoteValidation attribute.
Remote Validation in ASP.Net MVC 3: How to use AdditionalFields in Action Method
I am trying to write some kind of raw html to mimic what spring mvc tag produces after page rendering(and I do make them look exactly the same if you open them with a html element inspector). as I want to create dynamic input form using javascript. but it didn't work. it seems I had to use only what it offers: e.g. <form:input path="firstName" />.
to get the data binding working.
I thought the tag lib only help you to produce a html block that spring knows how to handle them in backend (action). from a web http perspective. what else it can send beyond a bunch of form data, and they should send the same thing. so I am really curious to learn what magic thing the tag lib dose beyond producing a html block.
the other thing I would like to know is where the model object is being hold when the form is being submit to a matched action. you know, you can get the model attribute by using #modelAttribute as the input parameter. is it in the original request object? or in the ActionRequest to which the dispatcherServlet build and put it. or even somewhere else?
thanks in advance.
I got it figured out. the raw html just works as spring tag does. as long as you are in the form tag block. you are okay to use raw html such as
<input type="text" id="abc" name="abc"/> just make sure name reflect your bean attribute path.
id is not mandatory and is just helping you to identify the very element. I guess I missed something when I work with the raw html by the time I ask the question. hope this helps for guys working with raw html approach, especially in case of dynamic input creation.
I'm using monorail, activerecord, and jquery. I have a form with a zip code textbox. I have in my active record class associated to the form:
[Property]
[ValidateNonEmpty]
[ValidateRegExp(#"/^\d{5}(-\d{4})?$/", "Invalid")]
public string ZipCode { get; set; }
As you can see, I'm using the ValidateRegExp attribute, which then auto-generates jQuery validate rules. The issue is that regular expressions are different in javascript than they are in C#. Javascript requires a / before and after the regex, whereas C# does not. If I put the slashes then the jQuery validation will work, but if they bypass the javascript validation and submit the form with js disabled (or if someone saves the object through another means like a test case) then it'll say the zip code is invalid because C# doesn't like the slashes.
So my question is, how do you please both javascript and C# with one regex? I would expect it to be smart enough to add slashes before and after just for the jQuery validation so that you could specify the regex in C# without the slashes but this is not the case it seems.
You should be specifying the regular expression itself, without the surrounding / characters.
If you are having problems with the client side, it would help if you'd include the JS error you see (if any), and actual generated JS code on the page that is being written out by Monorail to your page, and also the version of Monorail you are using.
As a side note, lets look at the code generating the JS validation rule from the validation attribute in JQueryValidator.cs
the relevant piece is at line 378 (as of current version of the codebase):
"function(value, element, param) { return new RegExp(param).test(value); }"
which points to the fact that the new RegExp(expression) is used, rather than the /expression/ format.
With that - it is clear that Monorail's jquery validator integration is ok.
I'm using jQuery 1.4.2. Not sure what version of MonoRail I'm using, the Castle.MonoRail.Framework dll says v2.0.0.0. I updated it within the last 3 months though so it's fairly new. The js that you're showing indicates that you have an even newer version than me, as it generates the following for me (if no slashes included in the ValidateRegExp expression):
"user.username":{ required: true , regExp: ^[\w ]{4,50}$ }
This obviously gives a syntax error in js, as it's not wrapped in quotes or slashes. I ended up creating a new RegExp validator with AbstractValidator as the base class to get around the faulty one that is in my version of MonoRail.
Do you know if this was an issue that was fixed in the last couple of months? Otherwise I can't explain how yours generates new RegExp in js and mine does not...
I enable client validation using the Html.EnableClientValidation method in my view. This client-side validation works great for text boxes, but I think I might have found a bug when used with dropdownboxes.
If you use the following construction Html.DropDownList( name, data, "Please choose..." ) without any ViewData-item with that name then client-side validation works great. If you look at the generated HTML code you will see that ASP.NET generated ValidationRules for it in the JSON block.
However, if I add a ViewData-item with that name then the ValidationRules for the client validation is empty!
In both cases, server-side validation works as expected. Bug or is there something that I am missing?
The solution is simple:
<%= Html.DropDownList("Username", CType(ViewData("Data"), SelectList), "Please choose...")%>
Client-validation does not work if you do it like this:
<%= Html.DropDownList("Username", "Please choose...")%>
In both cases, I use the same code to construct the ViewData item but it only works with the first statement.