Validation error messages are shown repeatedly in struts2 - struts2

I m new to struts2. I am doing client side validation for my form. The error messages for validations that i wrote in properties file are repeated each time i submit.
e.g.
First submit
username required
Second submit
username required
username required
Please tell me how to clear previous error messages?

You should give example from your code. There is a document about Struts2 client side validation and about Ajax Validation there writes:
clearValidationErrors(formNode) : Removes validation errors from a form
so you can try to do it.

If you are using a table on ur jsp to display the form, then make sure that the table is a parent of the form tag. If the table is a child of form tag, the validation messages wont get cleared each time. Making the form tag as a child of table tag would solve your problem.

If you are using the spring integration you have to define your bean as scope="prototype", then you get a new instance of your Action for every request.
It's a good idea to do this for every Action.

Related

How does rails handle form validations?

When a rails form fails on the the front end, how is the javascript handled? e.g. a numericality error fails or a required: true option is not fulfilled.
I would like to add a callback function to this. Is there any way to execute some javascript on the failure?
There is no javascript involved on the rendering of the errors on a rails form. The way the errors are displayed are determined by a function called field_error_proc, specifically ActionView::Base.field_error_proc. You can check Ryan Bates' railcast about it
If you are submitting your form via AJAX, you can attach a listener for the ajax:success event. Otherwise the only (ugly) way I can imagine is to do something like:
$(document).on('app:form-has-errors', function() { //do what you have to do} and on the view
<script>$(document).trigger('app:form-has-errors');</script> if the object in the form has errors (#your_object.errors.any?).
I don't think it is possible in another way since the submit and re-render on errors are complete http requests that will clear any events you might bind to the document.
Rails built in validation doesn't operate on the front end (client-side), it is done on the server.
If you want to do javascript validation you will need to find a gem for this or use a jQuery library, or write the validation code yourself.
The normal way form validation is done when using vanilla Rails is like this
The invalid form content is submitted to the controller
The controller uses the content to make the ActiveRecord object
The controller tries to save the object to the Database, kicking off a set of steps that starts with checking the object's validity
The model's validators say it's not valid and "decorate" the object with error messages specifying in which ways it is not valid.
The controller sees that the save failed and renders the view that had the original form in it, providing that view with the object, now with error messages.
The view when it renders the form checks the object for error messages, if it sees any it helpfully displays them to the user. It also populates the fields with the data that the user had previously entered that it gets from the object.

JSF PRG with validation error

I'm using JSF with the PRG pattern. (use in my navigation rules).
The problem is that the redirect is not done (i.e. a post followed by a get of the same page) when I got validation errors (ex : the mandatory value isn't set by the user).
The scenario is :
user doesn't put the mandatory value and submit the form
validation error occurs and the same view is shown with an error
message (no PRG)
the user set the mandatory value and submit ==> GO to the next page
(with PRG)
The user click back button => problem because no PRG was done in the
step 2. ==> Got a "Document Expired" screen in Firefox
Can anyone help me please?
Thanks in advance.
Stéphane
Just submit the form by ajax. It's a matter of adding
<f:ajax execute="#form" render="#form" />
to the command links and buttons. If you're using <h:message(s)>, then I assume that they are in the very same form, otherwise you need to add their client IDs to the render.
Validation errors while submitting the form by ajax won't generate history.

Struts2 and form validation of prefilled forms

I'm using the validate() - method of struts2 to validate the form input. In my struts.xml I can define a result with name "input" which is displayed if the validation fails. This for the context :-)
Now my question: the form I want to validate contains a selectbox which is filled out of a database. The first time the form is displayed everything works fine. But if I validate the form and the "input" - result is displayed, I get an IOException because of the iterator which outputs the db-result into my selectbox. Is there a solution from struts2 or do I have to use a plugin or something like that? Thank you!
When validation fails, it's often necessary to "reload" data for the form page. There's a FAQ entry that covers repopulating controls after validation, mainly detailing the Preparable interface (preferred) and the use of the <s:action> tag (there are some subtle gotchas that can pop up with this, but in general, it's also okay).

ASP.NET MVC3 Custom Unobtrusive Client Side Validation not preventing Ajax form post

I have a "change password" page that needs to hash any passwords entered on the page via Javascript before sending. To complicate it, the page is loaded via a jQuery load() call, and is submitted by a jQuery.Form ajaxForm() call. Had everything working in MVC2, but MVC3 is giving me trouble.
That is, I have a page with a "Change Password" link that when clicked, loads the change password page into a jQuery modal popup, then the form on the change password page get's submitted via the jQuery.Form library (Essentially just wraps a $.ajax call), and returns it's result into the modal same modal popup.
Essentially, I have a model with two properties, OldPassword and NewPassword. I have two hidden fields generated by by view for these. They hold the hashed value of two other fields, PrehashOldPassword and PrehashNewPassword, and get updated via keyup events (I know, this means it does a whole SHA256 hash on every keyup... inefficient, but got the job doen for testing). The key here is that the regex validation and required field validation needs to be executed on these Prehash fields, which exist on the client side only (As obviously I don't want to transmit these fields to the server in any way).
So I manually create these two and add on the data-val-* attributes to the elements, i.e. they are NOT generated by the MVC helpers, etc. I am guessing that this is where I'm missing something. When the form submits with all fields empty, all of the errors popup that should, but the form goes right ahead and submits anyway.
==
So the things I've tried:
Yes, the unobtrusive library parse() method already get's called to parse the AJAX loaded form contents, and it appears to get all of the data validation stuff correctly, since I see the errors show up as fields blur(), and when I hit submit (before the ajax request completes and replaces the content of the popup).
Possible note: this call to the unobtrusive library's parse method happens AFTER the AJAX successfully loads the change password page into the popup... the AJAX form submit binding is put on document.ready of the loaded content, ergo, the AJAX form submission binding MAY be binding prior to, and thus firing before, the validation calls that the parse method may bind to the submit event...
However, (1) I am doing this same sort of thing in other places without issue, the ONLY DIFFERENCE being that I am manually putting these data-val-* attributes on elements I am creating manually! And (2), if I cause some kind of error on the OldPassword or NewPassword fields, i.e. a required field validation error by not loading a value into them, they display their error, and successfully STOP the form from submitting through the jQuery.Form method.
So I think something has to be wrong here:
<input id="PrehashNewPassword" type="password" name="PrehashNewPassword" data-val-required="The password field is required." data-val-regex-pattern="<%= RegexHelper.PasswordRegularExpression %>" data-val-regex="<%= RegexHelper.PasswordRegularExpressionError %>" data-val="true" />
I know that jquery.validate is getting the rules right, since I DO see the errors. It's just not stopping the form from submitting when their is an error in these manually generated elements, unless I do something like this, and add a pre-submit callback on the form's AJAX submission:
$("#ChangePasswordForm").ajaxForm({
beforeSubmit: function () { if (!$('#ChangePasswordForm').valid()) { return false; } },
target: '#overlay'
});
While this works, it is kind of ugly and I believe it causes the validation to be called twice... Not a huge deal, but less than ideal. So is there some other call that I need to make in the unobtrusive library to bind these?
Not sure if you found the problem, but you may try to
return false
in there if the form is not valid...
.
.
.
if (!$('form').valid()) {
return false;
}
// JSON POST...
.
.
.
If that doesn't work, then you could try to use:
$.validator.unobtrusive.parse($("#dynamicData"));
after dynamically adding your custom inputs. "dynamicData" is the ID of an element wrapped around the form
above found from here: http://weblogs.asp.net/imranbaloch/archive/2011/03/05/unobtrusive-client-side-validation-with-dynamic-contents-in-asp-net-mvc.aspx
Out of interest, what happens if you just get the form to validate?
<script type="text/javascript">
$("form").submit(function (evt) {
// validate here should trigger invalid fields
$('form').valid();
// JSON POST...
// stop form submitting
evt.preventDefault();
});
</script>

How does validation in ASP.NET MVC 2 actually work?

I am trying to trace through why my ASP.NET MVC 2 validation isn't working, but I cant find enough about HOW it works to be able to do this.
I have followed the steps in this useful article by David Hayden which seems to be the best documentation currently out there, but nothing actually happens.
I get validation when i submit to the server (as I did since Preview 1 when i added data annotations to my model) but I'm not getting any client side validation.
How can i trace through to test? So far I have verified the following obvious things
MicrosoftMvcJQueryValidation.js and jquery.validate.min.js files are being downloaded
Html.ClientValidationEnabled = true
I cant see easily what is hooking up to which events to know quite how to debug it.
Here's what I've learnt:
MOST IMPORTANT
Your HTML Form must be created with the using directive, not just BeginForm and EndForm.
You must set Html.ClientValidationEnabled = true BEFORE you start your 'Form'
You must use Html.ValidationMessage for each field
You must set Html.ClientValidationEnabled = true on each partial control (ascx)
HOW IT WORKS (very simple overview)
When you do Html.BeginForm it creates a 'FormContext' in the ViewContext
When ValidationMessage helpers are used, metadata is put into the form context
When the form is disposed (by the using statement) it writes out all the validation code
MISC
I cannot seem to get validation working when I have a partial control, if that control uses a different model from the view that defines the Form.
You do NOT need to use Html.TextBoxFor or Html.ValidationMessageFor, you can use Html.TextBox and Html.ValidationMessage
In order for a field to be validated client-side you have to specify a call to Html.ValidationMessage/Html.ValidationMessageFor<> for the field (just like David did in the tutorial you linked) within the view. This is essentially a trigger to the client-side validation logic that you want to run validation for that field.
If there are situations where you don't actually want a validation message to visually appear for each field (i.e. by using Html.ValidationMessage), but would rather allow a summary to be the sole source of validation error messages (i.e. by using Html.ValidationSummary), you still need some way to "trigger" the validation to occur for the specific fields you want it to. This can be achieved by using the Html.Validate/Html.ValidateFor<> methods within your view. Those helpers won't render anything, but will simply register the specified field for client-side validation.
Both of those requirements exist since you might not want the client-side validation to automatically validate every property on your model object, since some of them might not even be part of the form that you're wanting validated.

Resources