Dynamically created elements are not validated on the client - asp.net-core-mvc

I have a table in my web application, which is populated from the model, where properties have attribute for validation:
[Required(ErrorMessage = "Please enter amount!")]
[DisplayFormat(NullDisplayText = "", ApplyFormatInEditMode = true)]
public decimal? Amount { get; set; }
When I press Submit, the field is properly validated on the client, displaying an error message, if the amount is left empty.
Now the user can add new TRs to the table using jquery. The new record completely imitates the existing records, e.g. when I inspect the Amount field for an existing TR:
<input class="form-control" type="text" data-val="true" data-val-number="The field Amount must be a number." data-val-required="Please enter amount!" id="Financials_1__Amount" name="Financials[1].Amount" value="1834.09"><span class="text-danger field-validation-valid" data-valmsg-for="Financials[1].Amount" data-valmsg-replace="true"></span>
Cf. to the same field of the dynamically added TR:
<input class="form-control" type="text" data-val="true" data-val-number="The amount must be a number." data-val-required="Please enter amount!" id="Financials_77e9f261-010a-4c7c-ae50-e3f6587a8c4e__Amount" name="Financials[77e9f261-010a-4c7c-ae50-e3f6587a8c4e].Amount" value="33"><span class="text-danger field-validation-valid" data-valmsg-for="Financials[77e9f261-010a-4c7c-ae50-e3f6587a8c4e].Amount" data-valmsg-replace="true"></span>
The records look very similar. Yet when I leave the required field empty and press submit, the value is not validated on the client, and the execution comes to the controller's action method. There ModelState.IsValid is false though. This is my first issue.
Here is the action method:
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<ActionResult> Edit(int contractorId, ContractorDetailsDto dto)
{
if (ModelState.IsValid)
{
...
}
return View(_contractorRepository.GetContractorDetailsViewModelByDto(dto));
}
As our ModelState is invalid, the same view is loaded. There the error is displayed in the validation summary, BUT NOT UNDER THE FIELD WITH THE INVALID VALUE. This is the second issue.
I have on my view:
#section Scripts {
<partial name="_ValidationScriptsPartial" />
}
How can I find the cause of my problems?

Answering for your main question. Can you try to execute next javascript code after you add new row
function refreshValidators(formSelector) {
var targetForm = $(formSelector);
targetForm.removeData('validator');
targetForm.removeData('unobtrusiveValidation');
targetForm.removeAttr('novalidate');
$.validator.unobtrusive.parse(targetForm);
}
Regarding your second problem I think you should create separate question for it as it unrelated to your main question. You need to find proper way how to add new rows in ASP.NET Core. For ASP.NET MVC we had next solution how to solve this task http://blog.stevensanderson.com/2010/01/28/editing-a-variable-length-list-aspnet-mvc-2-style/ . After googling BeginCollectionItem I found core analog solution, but it is pretty old and I didnt use it personaly.

Related

Custom Editor template based on ViewModel Dataannotation attribute MVC4

What I want to do is automatically add an image span after my input textboxes if the [Required] attribute decorates my ViewModel property be it an integer, double, string, date etc
For example, my ViewModel might look like
public class MyViewModel
{
[Required]
public string Name { get; set; }
}
and my View would look like
#Html.EditorFor(model => model.Name)
#Html.ValidationMessageFor(model => model.Name)
and the output would be something like
<input id="Name" class="text-box single-line" type="text" value="" name="Name" data-val-required="The Name field is required." data-val-length-max="20" data-val-length="The field Name must be a string with a maximum length of 20." data-val="true">
<span class="field-validation-valid" data-valmsg-replace="true" data-valmsg-for="Name"></span>
-- Note the automatically added span
<span class="indicator required" style="width: 11px;"></span>
I was intending to have some css that would show the image i.e.
span.required {
background-image: url("required.png");
}
Is this possible to do or do I need to create my own Helper method to implement this type of functionality?
Yes, it's possible, but in general I wouldn't recommend it, because templates are really there to customize type rendering, and you should be able to create templates without worrying if it overrides another template.
I would instead create a custom LabelFor helper, such as the one described here:
http://weblogs.asp.net/imranbaloch/archive/2010/07/03/asp-net-mvc-labelfor-helper-with-htmlattributes.aspx
or here:
http://weblogs.asp.net/raduenuca/archive/2011/02/17/asp-net-mvc-display-visual-hints-for-the-required-fields-in-your-model.aspx
A third option is to not do anything in MVC, but rather add some javascript that will add the indicator based on the standard MVC validation data attributes (if you're using unobtrusive validation). See the answer here:
https://stackoverflow.com/a/8524547/61164
What I did was to modify the jquery.validate.unobtrusive JS file to add a second container, specifically for your images, if there is a validation error.
var container2 = $(this).find("[data-valimg-for='" + escapeAttributeValue(inputElement[0].name) + "']"),
replace = $.parseJSON(container.attr("data-valimg-replace")) !== false;
container2.removeClass("img-validation-valid").addClass("img-validation-error");
Then don't forget to bind it to the model:
error.data("unobtrusiveContainer", container2);
Finally, empty it in the if (replace) code block:
if (replace) {
container.empty();
container2.empty();
error.removeClass("input-validation-error").appendTo(container);
}
else {
error.hide();
}
On success, remember to hide it:
var container2 = error.data("unobtrusiveContainer"),
replace = $.parseJSON(container.attr("data-valimg-replace"));
if (container2) {
container2.addClass("img-validation-valid").removeClass("img-validation-error");
error.removeData("unobtrusiveContainer");
if (replace) {
container2.empty();
}
}
If you take a look at the onError and onSuccess functions in the file, you should be able to find out where you can put them in.
In your view, add the following line of code to each form input there's validation for:
<img class="img-validation-valid" data-valimg-replace="true" data-valimg-for="<replace with field name here, ie. Name>" src="required.png" />
I've only tested this with the [Required] attribute, but it works. I'm also pretty sure you can use this for generating other stuff as well, not just images.

MVC matching ModelState keys to ViewModel collection

Is it possible to match a ViewModel property to the matching ModelState.Key value when the ViewModel is a (has a) collection?
Example: To edit a collection of viewmodel items, I am using the extension found here.
That adds a GUID to the id of the fields on the page.
example:
class Pets
{
string animal;
string name;
}
For a list of Pets, the generated html source is like this:
<input name="Pets.index" autocomplete="off" value="3905b306-a9..." type="hidden">
<input value="CAT" id="Pets_3905b306-a9...__animal" name="Pets[3905b306-a9...].animal" type="hidden">
<input value="MR. PEPPERS" id="Pets_3905b306-a9...__name" name="Pets[3905b306-a9...].name" type="hidden">
<input name="Pets.index" autocomplete="off" value="23342306-b4..." type="hidden">
<input value="DOG" id="Pets_23342306-b4...__animal" name="Pets[23342306-b4...].animal" type="hidden">
<input value="BRUTICUS" id="Pets_23342306-b4...__name" name="Pets[23342306-b4...].name" type="hidden">
So when this gets bound on post, the ModelState gets loaded with all the form fields.
In ModelSTate.Keys, there is:
Pets[23342306-b4...].name
Pets[23342306-b4...].animal
Pets[3905b306-a9...].name
Pets[3905b306-a9...].animal
Everything good so far, but I am doing some business logic validation, things like, cant add new animal if one exists with the same name. In that case, I want to be able to highlight the input field that is in error.
So if my create function fails, it will return an error/key value pair like this:
{ error = "Duplicate Name", key="name" }
So I at least will now what property caused the problem.
But since my repository functions don't know about the view field ids, how can I match the key "name" to the appropriate ModelState key (in this case, either Pets[23342306-b4...].name or Pets[3905b306-a9...].name)?
If you used the built in functionality of MVC for displaying collections (Html.DisplayFor(m => m.Pets) or Html.EditorFor(m => m.Pets)) with appropriate display/editor template, MVC would render something like this:
Pets[0].name
Pets[0].animal
Pets[1].name
Pets[1].animal
This maps to IEnumerable<Pets> and you know that first item has index of 0, second item 1 etc.
So if the second item has an error, you can set error for the ModelState key "Pets[1].name" for example.
If you are using the Html.BeginCollectionItem extension method, like I was, I was able to get around this by not using the GUID. I need the dynamic add and delete, but I was always looking up known items, persons that have an ID, which I had in my editor. So instead of using the GUID, I just assign the ID (uniqueId) in the code below. I could then find the key because I knew it was Person[234232]. Of course if you are adding new items and not displaying selected items, it might not work for you.
public static IDisposable BeginCollectionItem(this HtmlHelper html, string collectionName, string uniqueId)
{
var idsToReuse = GetIdsToReuse(html.ViewContext.HttpContext, collectionName);
string itemIndex = idsToReuse.Count > 0 ? idsToReuse.Dequeue() : uniqueId;
// autocomplete="off" is needed to work around a very annoying Chrome behaviour whereby it reuses old values after the user clicks "Back", which causes the xyz.index and xyz[...] values to get out of sync.
html.ViewContext.Writer.WriteLine(string.Format("<input type=\"hidden\" name=\"{0}.index\" autocomplete=\"off\" value=\"{1}\" />", collectionName, html.Encode(itemIndex)));
return BeginHtmlFieldPrefixScope(html, string.Format("{0}[{1}]", collectionName, itemIndex));
}

How to add unobtrusive validation for html template fields whats not in the model

i got a template created for custom zip code field.
My template code is below:
#{
string model = Model ?? string.Empty;
string zipFirst = "";
string zipSecond = "";
if(!String.IsNullOrEmpty(model) && !String.IsNullOrWhiteSpace(model))
{
var values = model.Split('-');
if(values.Count() == 2)
{
zipFirst = values[0] ?? string.Empty;
zipSecond = values[1] ?? string.Empty;
}
}
var pName = ViewData.ModelMetadata.PropertyName;
var zipAreaId = "#" + pName + "zipcodearea";
}
<div id="#(pName)zipcodearea">
<input type="text" maxlength="5" id="zipcodefirst" name="#(pName)codefirst" value="#(zipFirst)" style="width:136px"/> -
<input type="text" maxlength="4" id="zipcodesecond" name="#(pName)codesecond" value="#(zipSecond)" style="width:120px"/>
#Html.HiddenFor(m => m, new { #class = "generatedZipField"})
</div>
<script type="text/javascript">
jQuery(function ($) {
$('#(zipAreaId) #zipcodefirst').autotab({ target: '#(pName)codesecond', format: 'numeric' });
$('#(zipAreaId) #zipcodesecond').autotab({ previous: '#(pName)codefirst', format: 'numeric' });
$('#(zipAreaId)').zipcode();
});
</script>
And i use it like this:
[UIHint("ZipCode")]
[Display(Name = "Zip Code")]
public string Zip { get; set; }
Like you see in my template i got two fields whats not included in the model.
It is #zipcodefirst and #zipcodesecond.
What i need to achieve is to have two separate fields for full us zip code.
When user fill both fields im using jquery widget for merging them into one string and inserting it into hidden field in template. after form submited value in hidden field getting sent into server.
Whats the problem?
I need to add mvc unobtrusive validation for them two fields whats not in the model #zipcodefirst and #zipcodesecond.
validation rules
zipcodefirst field must be filled in first
then zipcodefirst field is filled you can fill second field
second field must have 4 digits in it
first field must have five digits
cant fill second field while first one is empty or incorectly filled
Im strugling with validation part for quite a while now.... :(
How i could achieve that thru mvc3 unobtrusive validation tools?
any help will be highly apreciated guys.
Add unobrusive data data validation on the textbox by adding data-val="true" and use a regular expression for your zip code.
<input type="text" data-val="true" data-val-regex="Invalid zip code format" data-val-regex-pattern="YOUR REGEXP HERE" />
UPDATE
If you also want it to be required you can add the data-val-required attribute.
<input type="text" data-val="true" data-val-requred="Zip code is required" data-val-regex="Invalid zip code format" data-val-regex-pattern="YOUR REGEXP HERE" />
More information about validation in MVC 3:
http://bradwilson.typepad.com/blog/2010/10/mvc3-unobtrusive-validation.html

play framework: how to repopulate form on validation-failure when using datamodel?

I'm building some crude CMS-like functionality (to get acquinted with Play Framework). For this test-case I've build 2 pages, 1 for listing tags and 1 for creating/editing/saving tags.
The flow is like this (routes-file):
#list tags
GET /tags Application.listTags
#view/edit existing tag
GET /tag/{<(?!new$)(.+)>name} Application.showTag
#new tag
GET /tag/new Application.showTag
the create/view/edit page displays a form which gets it's values from a tagDTO.
The normal flow works without problems, but when the form gives validation-errors (e.g: the tag-name must exist) I want to display the page again, repopulating the form with the edited values.
For this (following the Play Framework conventions) I could use the 'flash'-object which contains these last values, but the form is already bound to the tagDTO (which is null on redirect) instead of the 'flash'-object.
First the code:
Application.java
.....
public static void showTag(String name) {
TagDTO tagDTO = TagDTO.buildDTOFromModelOrNew(name);
render(tagDTO);
}
/**
* Save tag and redirect to Show
*
* #param name
* #param displayname
* #param isnew
*/
public static void saveTag(
#Required(message="Name is required") String name,
String displayname,
boolean isnew)
{
checkAuthenticity();
if(validation.hasErrors()) {
params.flash();
validation.keep();
showTag(null);
}
//fetch tagDTO based on backend or create new if not exist
TagDTO tag = TagDTO.buildDTOFromModelOrNew(name);
// Append / Overwrite values
tag.displayname = displayname;
tag.name = name;
//save result to model
TagDTO.buildAndSaveModelFromDTO(tag);
flash.success("Thanks for " + (isnew?"creating":"updating") + " tag " + tag.name);
//redirect to show
showTag(tag.name);
}
And ShowTag.html
#{extends 'main.html' /}
#{if flash.success}
<p class="success">${flash.success}</p>
#{/if}
#{ifErrors}
<p class="errors">Oops...</p>
#{/ifErrors}
#{form #Application.saveTag()}
#{authenticityToken /}
<p>
<label for="name">Name: </label>
<input type="text" name="name" id="name" value="${tagDTO.name}" />
<span class="error">#{error 'name' /}</span>
</p>
<p>
<label for="displayname">Displayname: </label>
<input type="text" name="displayname" id="displayname" value="${tagDTO.displayname}" />
<span class="error">#{error 'displayname' /}</span>
</p>
<p>
<input type="hidden" name="isnew" value="${tagDTO.isnew}" />
<input type="submit" value="Submit your comment" />
</p>
#{/form}
Now I could think of some ways to make it work, but none really elegant:
bind the form to the flash-object (or params-object) and populate the flas/params- object from the tagDTO
on validation-failure, refetch the tagDTO (not avail anymore so DB-call necessary) and overwrite values in tagDTO with values available in flash-object, bind form to tagDTO.
like 2, but using some sort of cache to quickly fetch tagDTO (so no need for db-call)
Some general mechanism to (de)serialize tagDTO from/to the session.
In short, I don't like any of them really.
What would you consider to be a best practice in this situation? Or is there any functionality in the Play Framework that I'm missing?
This is where the explicit render calls comes handy. Retain the form values from previous submission and give it back (if validation fails) as follows,
checkAuthenticity();
if(validation.hasErrors()) {
render("#showTag", name, displayname, isnew);
}
This will avoid the extra redirect (307 in case of Play!) that would have happened if you had called 'action from another action'.
Render the form again and avoid the redirect is a solution. I think it's OK if a user press F5 he will get the error again. But I think you should create a reload/cancel button, so the user can dismiss all the information.
To have always the correct URL you can do the following in the routes.conf:
GET /tag/create TagController.create
POST /tag/create TagController.insert
The flash solution has the disadvantage that your cookie can get really big.

Adding profile fields to registration form asp.net mvc3

I am new to mvc and would like to add an additional field to my registration page that is simply a dropdownlist bound to a table in my model (a table of organization names and IDs). However, in my default application I see that the AccountController is using the RegisterModel model to create the register form view. This is fine, I don't want to disturb this. But I want to add a new select box on the page bound to a different model (my model with the organizations). How do I accomplish this?
I've found other posts that suggest I create a wrapper model for both my model and the RegisterModel, but this isn't working. My wrapper model looks like this:
public class RegisterPeopleModel
{
public RegisterModel reg { get; set; }
public fwfEntities fwf { get; set; }
}
And now the field validator for password is no longer working. The code in the view:
<div class="editor-field">
#Html.PasswordFor(m => m.reg.ConfirmPassword)
#Html.ValidationMessageFor(m => m.reg.ConfirmPassword)
</div>
Now renders this:
<div class="editor-field">
<input data-val="true" data-val-equalto="The password and confirmation password do not match." data-val-equalto-other="*.Password" id="reg_ConfirmPassword" name="reg.ConfirmPassword" type="password" />
<span class="field-validation-valid" data-valmsg-for="reg.ConfirmPassword" data-valmsg-replace="true"></span>
</div>
Notice that the IDs of the span and input no longer match. The form no longer works at all. This is leading me to believe I'm taking the wrong approach. Is there a better way of getting my select list on the page bound to a different model?
Thanks in advance.
Is there a better way of getting my select list on the page bound to a
different model?
If the model doesn't meet the requirements of the view you should modify this model. In ASP.NET MVC it is a good practice to design view models and pass only view models to views and not domain models (like for example EF autogenerated classes which is what this fwfEntities type seem to be). So design a view model which contains only the properties needed by your view and have your controller action query the database in order to fetch the model then map the model to a view model and finally pass this view model to the view.
Without seeing RegisterModel my guess is that ConfirmPassword has not got a required attribute for example;
[Required(ErrorMessage = "A password is required")]
public string ConfirmPassword { get; set; }
oh I believe the period in the id is replaced with an underscore so as not to cause issues with Jquery.

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