Weird Behavior Of Angular With TextBox Required - javascript

I have 2 textboxes, one which is required and the other one which is not required.
If we add text in the required text box, say "ABC", then remove the content, the ng-model is set to undefined
If we add text to the non required field and remove the content, the ng-model is not to empty string "".
Here is a plunk about the behavior I've explained above. Please use the console to look at the result.
http://plnkr.co/edit/XgQBfcyRF3OwG1qC0gXb?p=preview
Why is there a difference in setting the ng-model between the two?

It is seems to be by design, and has to do with a consistent behavior of validated form values.
There isn't anything on this behaviour in the docs, AFAIK.. It is implied here -> https://github.com/angular/angular.js/blob/master/src/ng/directive/input.js#L1045
With angularJS validation, if a value entered on field is allowed, that becomes the model's value (as any other bound value would behave). If it isn't, the only way to be consistent is to set the value as undefined (as no allowed value is in the field). The two other options would be to keep it's last valid value, or keep binding the wrong value, only triggering the flags for invalid field, and form. Both these solutions are bad - leaving the last value is probably not wanted (if you were to use the values disregarding the state of the form, it would lead to errors) and allowing for invalid values is a terrible sin ;) (you couldn't trust the validation service to help prevent buggy use of wrong types)
Although it may seem strange or even inconsistent, it really isn't. I have slightly modified your plunkr to validate for a number, which I believe makes it clearer why it is this way: http://plnkr.co/edit/9gJmblUn9MUUeFt5lWJZ?p=preview.
So, in reality there is no difference - only in your second input an empty string is considered a valid, thus accepted value for that field.

Related

Object properties being wiped by fast changes

I have a form that uses server-side validation and coercion.
In Vue, the state of the form fields is held in an object called instance, on the data object. Each field's value is represented by a property of instance.
onChange of any field, instance is posted to an API method that returns validation results and a coerced dataset (coercion does things like adding spaces to phone numbers, capitalising postcodes etc.).
Vue takes the response and iterates through the coerced data, replacing the properties of instance. If a field has not yet been reached by the user it is skipped (There is a reached object that keeps track of which fields the user has made it to).
The issue that I'm having is that occasionally (when entering data extremely quickly from one field to the next) the input of the current field gets cleared when the coerced data is returned from the previous one.
Initially I thought that there must be some issue with the reached logic, and that the null data returned for the field that the user is working on is overwriting the current input. But this is not the case; I can see in my logs that fields are being skipped yet the input is still clearing.
I'm starting to think that this might be a bug with Vue. Or at least, something specific to how Vue handles the data/dom elements that I need to account for. Is there a way that setting instance.foo could cause instance.bar to be reset?
//this is called onChange for any field.
change: function(e) {
this.$set(this.instance, e.name, e.value);
this.setReached(e.name);
this.validate(true);
},
validate: function(reachedOnly) {
axios.post(this.validateUrl, this.getFormData(false)).then(response => {
this.allErrors = response.data.errors;
this.setFormData(response.data.values, reachedOnly);
this.fieldNumberValidated = this.fieldNumberReached;
});
},
setFormData: function(data, reachedOnly) {
for (var fieldName in this.fieldNames) {
var value = data[fieldName];
if(reachedOnly && !this.reached[fieldName]){
console.log('skipping - '+fieldName);
continue;
}
if (value && value.date) {
value = value.date.replace(/\.\d+$/,'');
}
this.$set(this.instance,fieldName,value);
}
},
* UPDATE: *
I think I know what's happening now.
Field A triggers change()
Data gets sent for validation
User starts inputting into field B
Validated data gets returned. And set on this.instance.
Vue skips field B because it isnt in this.reached
BUT this.instance is being updated and redrawn.
Field B may have text entered in its input but it hasn't been added to this.instance because it hasn't triggered change() yet. So this.instance is redrawn based on field B having no value, which in turn updates the input and wipes whatever may have been in there.
This isn't a full answer but just some thoughts.
I'm not certain about why a field is being cleared, however I would like to point out a concurrency issue you may have. If you're calling the API for each keypress, you're not guaranteed that they will respond in the correct order, and it could be that you are setting the form data to an old validation response which would cause you to lose any text entered into the textbox since the request was fired. Also it's generally a good idea not to spam the server with too many requests.
At a minimum you should probably debounce the API calls, or use blur instead of change event, or you could implement some logic that cancels any pending validation request before firing another one.
Is there any particular reason why you are using this.$set? It should only be used if you're adding a property to an object.
Initially I thought that there must be some issue with the reached logic, and that the null data returned for the field that the user is working on is overwriting the current input. But this is not the case; I can see in my logs that fields are being skipped yet the input is still clearing.
It might be better to log when you set the data, instead of when you skip. The issue is some fields are being cleared, so log every time they are set so you can identify times when the field is being set when it shouldn't be.
Is there a way that setting instance.foo could cause instance.bar to be reset?
Not that I'm aware of. It would help if you can provide a MCVE.
I eventually solved this by having 2 different events on my input fields - one for input that updates instance and another on blur that sends the validation request.
change: function(e) {
this.validate(true);
},
input: function(e) {
this.$set(this.instance, e.name, e.value);
},
This ensures that the properties of instance are always in line with their related input fields, and so nothing gets erased when instance is redrawn.

How to know if field is masked due to field level security?

is there a way to find out if field level security has been applied to a field in DCRM 2013?
I'm looking for something like:
Xrm.Page.getControl("controlName").isMasked()
You can use Xrm.Page.getAttribute("attributeName").getUserPrivilege(), which returns an object containing three booleans:
canRead
canUpdate
canCreate
In your case you could check the value of .canRead to figure out whether the user can see the contents of the field or not.

How to properly clean form with invalid input from AngularJS controller?

I have an AngularJS form that contains - among other fields - one of type url. The latter is important as this forces the corresponding input to be a valid URL.
Under certain conditions (for instance, a modal dialog with such a form is to be closed), I want to clear that form programmatically. For that purpose, I implemented method reset that basically clears the corresponding form model by setting $scope.formData = {}. Thus, it sets the form model to a new, blank object.
While that assignment clears all valid fields in the rendered HTML form, it does not clear invalid fields, like an invalid URL. For instance, if the user would provide invalid input ht://t/p as URL, that input would not be removed from the rendered form.
I think this is due to the fact that any invalid URL is not reflected by the model - such an invalid URL just wouldn't "make" it to the model because it does not pass validation in the NgModelController#$parsers array. Thus, in the model - there is no URL at all. Consequently, resetting the form model to {} cannot actually change the model's URL as it has not been set yet.
However, if method reset explicitly sets field $scope.formData.url = "", the invalid URL will be cleared properly (at least, the rendered form won't show it anymore). This is caused by the explicit change of the URL in the model. However, now, model variable formData.url contains the empty string (well, not surprisingly), while by using = {}, all fields would be undefined instead.
While assigning individual fields to "" works as workaround for simple forms, it quickly becomes cumbersome for more complex forms with many fields.
Thus, how could I programmatically reset the form efficiently and effectively - including all invalid input fields as well?
I created a Plunker at http://plnkr.co/c2Yhzs where you can examine and run a complete example showing the above effect.
Specify the type of your button as reset. That will not only call the ngClick function, it will also clear the content of the HTML form.
<button type="reset" ng-click="resetFormData()">Reset</button>
I think this solution is moderately elegant: your plnkr reviewed
The big difference is the initialization of your model object.
I think things gets messed up when a variable becomes undefined, it doesn't get updated anymore.. it should be connected (veeeery) deeply with how validation works (docs link)
Returning undefined in that case makes the model not get updated, i think this is exactly what happens behind the curtain
PS: you can recycle resetImplicitly for all your forms in the webapp :)
After trying several answers without success in similar questions, this worked for me.
In my controller:
$scope.cleanForm = function() {
$scope.myFormName.$rollbackViewValue();
};
Just call with some ng-click or any way you want.
Cheers
The Thing is tag is of type "url" which means
if user will enter specifically a valid url then only it will set values of model
If user will expicitly reset it which means setting model values to "" will again make textbox empty .
It is looking like it is setting the values but actually not ,so when you set its value to "" .Angular will set modal value to ""
Lets take another example : put replace "text" with "email"
<input type="email" ng-model="formData.name" />
<br />URL:
<input type="url" ng-model="formData.url" />
<br />
In above code If you will enter invalid email it will not set the values of email's model.
You probably need to make a copy of the model in its pristine state and set the model to pristine when you reset.
There's a good example here:
http://www.angularjshub.com/examples/forms/formreset/
The url form fields are passed into the model only if they are valid. Thus in case of an invlaid-url entry in the form, the scope variable is not assigned with the model and clearing the forms entry by assigning an empty object to the model will still persist the value at the UI front.
The best alternative to this is to assign the model associated with the form data with a null. A similar answer appears here:
https://stackoverflow.com/a/18874550/5065857
ng-click="formData={};"
just give like this ,
<button ng-click="formData={}">(1) Reset Full Data: formData = {}</button>
Reset your form data directly in ng-click itself.

Force re-validation in jsViews if data-linked value doesn't change

I ran into an issue while using jsViews with validation (using code from jsviews.com/#samples) and jQuery UI Autocomplete:
I have a converter (convertBack) on the field that transforms the entered text back into a GUID based on a dictionary. It returns null if the field is empty or invalid.
The issue is that jsViews doesn't notice the update from one null value to the other (i.e. blank to invalid, and vice versa). I tried to fix this by adding a call to refreshValidates() on the validation tag to the DOM onChange manually, but any invalid value entered gets deleted.
Question: Is there a way to achieve re-validation in jsViews natively?
I changed the jsViews validation code to allow checking displayed value:
[End of onAfterLink]: It passes the current (displayed) value, not only the converted (which is null in both cases):
(...)
tag.validate(tagCtx.args[0], tag.linkedElem.val()); // Validate initial data
tag.linkedElem is the HTML element on which you are doing 2-way data-binding, (and validation).
So if you just want to get the current value of the input element, yes, tag.linkedElem.val() is good.
Additional response added following your comment below:
Looking at your jsfiddle: http://jsfiddle.net/w43hD/1/
You are using
data-link="{validate DictionaryValue inDictionary='dictionary' convert='fromGuid' convertBack='toGuid'}"
which will trigger validation when the DictionaryValue it is binding to changes. But you are mapping both invalid user entry strings and the empty string to the same DictionaryValue of null. So of course switching from invalid to empty string does not trigger validation.
You can change your getKey converter to map the empty string to something other than null, e.g. "" - and then it works. See updated version: http://jsfiddle.net/w43hD/2/

Is there a way to set an ASP.Net hidden field value to NULL using Javascript?

I'm looking at tons of examples of how to set a hidden field value using Javascript. My question is actually, can you set a hidden field value to NULL using Javascript / jquery, then have that NULL reflected in the value on serverside?
Every time I try and set null, I get back blank.
I have a specific requirement to know the difference between NULL and blank, and the only allowed mode of communication between client a server is a runat=server hidden field.
Any help would be greatly appreciated.
I can think one way to make it null, totally remove the value attribute, or even harder remove the name attribute so it will not post back, and then add it back when this input have again value.
Or set to that value a parameter like 'null' and check for that on code behind.
Think, that the null is one more parameter on your list, nothing more nothing less, and the values that are post back are all actually strings. So the only conflict that you can have is you set it "null" is in case that you have a text, but on text you can compare with no text at all and decide if this can be null or empty... is decisions that you must make.

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