Best way to get values using ngFormController - angularjs

This can't be correct, perhaps my google has gone off the rails but for the life of me I can't find any documentation to return all $valid = true values using the FormController. Does this functionality exist? I'm trying to marshall information from a form and send it to my web service but I wan't to make it something sensible before doing so. Currently I'm looping through all the properties in the FormController for a given form and looking to see if it doesn't start with $, and $valid = true and pushing it into an array like so:
angular.forEach(form,function(data,key)
{
if(key.indexOf('$') === -1 && data.$valid)
{
var item[key] = data.$modelValue;
clean.push(item);
}
})
Real basic, but I'm totally stumped (and can't fully believe) that this doesn't exist already in the angular API somewhere. Am I missing something? I'm still learning a lot about angular and am getting the feeling that much isn't really documented but perhaps i'm missing something quite basic. Thanks for reading!

This is not what ngFormController is used for (for validation and custom directive scripting). If you need to collection form data to send to server all you need is do is to make use of ngModel directives:
<form novalidate ng-submit="saveUser()">
<input type="text" ng-model="user.name">
<input type="text" ng-model="user.email">
</form>
and in controller saveUser handler you can access form data like
$scope.saveUser = function() {
console.log($scope.user); // {name: "Thomas", email: "mann#ga.com"}
// use $scope.user data to send to server
};

You just need to use ng-model. Angular won't populate the model until the value in the form is valid, so you don't need to check $valid manually.
Ex:
<input type="text" ng-model="myData" ng-minlength="3" required>
{{myData}}
You'll see myData isn't populated until you've entered at least 3 characters.

Related

bind email containing apostrophes to angular model

I have an input type email that I validate against my own custom regular expression. It in turn is bound to an angular model something like:
js
$scope.user = {};
html
<input type="email" ng-model="user.email" />
I would like for the email to allow apostrophes but the email doesn't bind to the model unless it passes the built in html5 validation. I'd like to override or switch off this validation since I have my own custom regex in place.
I've tried adding the novalidate tag to the form wrapper and also adding a pattern to the input but not getting anywhere. Please see jsfiddle:
http://jsfiddle.net/HB7LU/19499/
Any ideas greatly appreciated
C
EDIT: The reason I'm not using type="text" is because I want the email keyboard set to be there when accessing from mobile.
Angular do not support the apostrophe(') in email Id , if need to valid the apostrophe in angular, need to change in angular file regular expr
(/^[A-Za-z0-9._%+-]+#[A-Za-z0-9.-]+\.[A-Za-z]{2,4}$/)
to
/^[A-Za-z0-9._%+'-]+#[A-Za-z0-9.-]+\.[A-Za-z]{2,4}$/.
It will Work perfectly.
If you already have a regex for validation, you could set the type of the input tag to "text" so that then it would not do any validation and then the regex you have already created could be used to do the validation you want. Also, this will allow you to change the validation method if you ever decide to change how you want validation to work.
Here's the tag:
<input type="text" ng-model="user.email" />

AngularJS ng-required better implement from controller?

I'm thinking of a good way to implement ng-required.
Let's say I have a bunch of inputs with ng-required in my app.
<input type="text" id="one" />
<input type="date" id="two" />
<input type="radio" id="three" />
<input type="checkbox" id="four" />
I would like to do something in a controller, where I could pass an array of required fields. I'm thinking that if I made an array of elements such as:
var myEl = angular.element( document.querySelector( '#some-id' ) );
and some how set the required property that way.
I write a directive which would decide from an array if the field is required, if it does not exist in the array, it's not required if it does, it's required.
Ultimately, I would like to have an array that allows passing of fields in such a way:
var reqArray = ('#id', ('#id1' || 'id2')) etc.
Works the same as conditional logic operators:
#id is required
#id1 || #id2 is required, but not both.
Not sure where to begin, or if it's feasible in Angular.
This would make it easier to modify required fields in large applications without having to modify the actual html.
It can be done, but angular already provides its own ways to validate forms. Some brief details:
The form tag must have a novalidate attribute in order to prevent HTML5 validation. <form name="myForm" novalidate>
With that, now angular can take charge of the validation by adding a "required" attribute to your inputs <input ng-model="myModel" type="text" required>
By this point, angular has taken control of your validation, it can also validate other HTML5 attributes like pattern. <input pattern="[0-9][A-Z]{3}" type="text" title="Single digit followed by three uppercase letters."/>
I suggest you take look at this official guide (also take a look at the directives guide on that same site, I wanted to link it but I don't yet have the rep).
That being said, what you are trying to accomplish is also possible, but rather redundant since you would have to add an attribute to your inputs anyway (the directive, and angular is able to validate already) and also require ngModel in the directive.
I made this plunkr to show you how to do it, but take notice of the extra work needed in order to validate something that angular already does natively, I'd leave this kind of work for expanding on validations, like comparing items or models.
Also, querying a selector directly like in your suggestion is not considered "the angular way". A better way would be to add the directive to your form element and access the element through the 'element' parameter in the directive.
Hope this helps.

AngularJS Initialize model directly from view using strongly typed object in asp.net MVC

Is it not possible to use strongly typed objects in asp.net mvc to initialize ng-model properties as currently the view value is getting cleared as soon as ng-model property is getting bind to view.I know it will work if I initialize that value form model but that would mean I will have to make a get request just to pull the model value ,but what if I want to leverage existing strongly typed model binding feature of asp.net mvc ??
You can make you use of ng-init. For example you have:
<input type="text" ng-model="name">
You can use it as:
<input type="text" ng-model="name" ng-init="name='#Model.Name'">
Which on the client side will get converted to:
<input type="text" ng-model="name" ng-init="name='Abdel'">
And you will be able to use it... Hope this helps!
We can do this by using a value provider, which can be injected in controller or service:
var app = angular.module('app', []);
app.value('mystuff', #Html.Raw(JsonConvert.SerializeObject(Model)));
app.controller('HomeController', ['mystuff', function(mystuff) {
}]);

How to use angularjs form validation in a non-angular SPA app

I wonder if anyone can help. On the surface of it, my question title may sound kind of stupid! I'm trying to use angularjs form validation in a non-angularjs application! Let me try to explain ...
We have a 'traditional' web app. Its not an SPA. The backend is java, and the java app server manages the session and the data within. Each page is a full http request/response. (There are a small number of ajax request/responses, but these are to add some bling to the page, rather than it's core functionality). In this respect, the architecture of the app is very traditional/old-skool, in that the server-side java code is responsible for generating the markup and populating form field values from it's version of the model data held in it's session store. (I think this is the crux of the problem)
The app is predominantly a HTML form based application, and to enhance the UX we have written some javascript field validators based around jQuery. For a number of reasons these have started to get a bit out of control, and we are exploring alternative options.
A simple google search finds countless jQuery plug ins for form validation. We are looking at these, but random jQuery plug ins are not our favoured approach (we tend to steer clear of 'somebloke.com' plug ins because we can't guarantee how well they're written, browser compatibility, future maintenance, how well they work with other plug ins etc - we've had our fingers burnt with this kind of thing before)
So we are looking at other approaches, and are currently exploring the use of angularjs.
Being able to 'gently introduce' angularjs into our architecture has some advantages. It's from a stable best-of-breed organisation (ie. it's not 'somebloke.com') so is well supported and maintained. It encourages us to write our js in a very modular & testable manner (our current rats nest of jQuery plugins, callbacks etc is far from that!). angularjs form validation is based around html5 standards and is declarative and semantic. It gives us a way forward for migrating our other jQuery based code to something better (angularjs directives). And overall, if we can layer angularjs into our current app, it gives us a good foundation for converting the app to a modern SPA at some point in the future.
Rewriting the entire app as an angularjs (or any other mv* framework) SPA at this point in time is not an option, so as mentioned above, we are looking at introducing small bits of functionality at a time; and today's challenge is form validation.
So, that's the background.
I've stripped out our current js client side validation, and our server-side java code is generating markup like this:
<form method="POST" action="/renew">
<input name="firstname" type="text" value="alf" />
<input name="surname" type="text" value="garnet" />
<input name="age" type="number" value="88" />
<input type="submit" />
</form>
(where the values for the input fields have been populated server-side from the model held by the server)
I've added the angularjs library to the page, and have got form validation working as follows:
<form method="POST" action="/renew" novalidate name="renewForm"
ng-controller="yourDetails" ng-submit="submitForm(renewForm, $event)">
<input name="firstname" type="text" value="alf" required ng-model="firstname"/>
<input name="surname" type="text" value="garnet" required ng-model="surname"/>
<input name="age" type="number" value="88" required ng-model="age"/>
<input type="submit" />
</form>
app.controller('yourDetails', function($scope) {
$scope.submitForm = function(form, $event) {
if (!form.$valid) {
$event.preventDefault();
return false;
}
};
});
This is a reasonable starting point. Broadly speaking it works in that angularjs is handling the form validation and submission. The submitForm method is executed, and if the form is not valid then the if block is entered and the form submission is cancelled. From here I can see it would be easy to add in the field error messages etc using ng-show etc.
The problem however is the use of ng-model on each html field. As I understand it I need to use this so that angularjs binds the field to the form, and can therefore track each fields valid status.
However, ng-model also appears to setup the 2-way data binding and sets the value of the field to it's version of the model data ... which is empty. For example:
Our server-side template might contain this:
<input th:field="*{firstname}" type="text" required ng-model="firstname"/>
Which might generate this markup:
<input name="firstname" value="alf" type="text" required ng-model="firstname"/>
The markup that gets served to the client includes value="alf"
But then angularjs steps in and sets up 2-way binding for the field. Because we don't have a firstname property in the angularjs scope, it initialises one with a blank value, and sets that blank value in the DOM of the field.
This results in the page being rendered by the browser with blank values in the fields, even though server-side we have values in the model, and the server has correctly generated the markup etc.
So, I think I understand the core problem and why it's happening. My question is, can I do angularjs form validation without the ng-model attribute on each field, or is there a version of the ng-model directive that only does 1-way binding - specifically DOM -> model
Any help would be very much appreciated;
Thanks
Nathan
When generating your form at server side, you can initialize your model with ng-init:
<input ng-init="firstname='alf'" th:field="*{firstname}" type="text" required ng-model="firstname" />
OK, #Alexandre's answer was almost right, and it was his answer that pointed me in the direction of my final solution (so he should get the credit for this really :) )
ng-init does work as #Alexandre has suggested. The reason I couldn't get it to work was that I was trying to use it on a number field.
The following works because the value being set on the model with ngInit and the html input type are both text/string:
<input ng-init="firstname='alf'" th:field="*{firstname}" type="text" required ng-model="firstname" />
I was trying it on the age field as follows:
<input ng-init="age='88'" th:field="*{age}" type="number" required ng-model="age" />
This does not work because the age property was being set on the model as a string, but the html input type is a number. The following does work:
<input ng-init="age=88" th:field="*{age}" type="number" required ng-model="age" />
This led me to realise that the value being set on the angular model needs to match the data type of the html input type (certainly true of chrome, not sure about other browsers) (ie. string properties in the model - even if they are parse-able as numbers - cannot be used in a html number field with ngModel)
With this in mind, I decided there were 2 options. I could either do it server-side in the code that generates the markup:
<input ng-init="age=(some-potentially-complex-logic-to-workout-whether-its-a-string-or-number)" th:field="*{age}" type="number" required ng-model="age" />
Or I could do it client-side with a custom directive. In the end I went with a custom directive because a) it meant I could have a go at writing a directive (all part of the learning :)) and b) I realised there might be other cases that need special consideration which might make doing it server-side even more complex (ie. select fields don't have a value, they have a selected index of which you need to get it's value; radio buttons all have a value but you only want to set the value of the checked radio)
Here's what I came up with:
angularApp.directive('lvInitializeValueOnScope', function() {
return {
restrict: 'A',
link: function(scope, element, attrs, controller) {
var propertyName = attrs.name,
propertyValue = attrs.value,
elementName = element.get(0).tagName.toLowerCase(),
fieldType = ( elementName === 'input' ? attrs.type.toLowerCase() : elementName ),
// set expression to assume propertyValue is a string value
expression = propertyName + '=\'' + ( !!propertyValue ? propertyValue : '' ) + '\'';
// if the input field type is number and propertyValue is parse-able as a number
if (fieldType === 'number' && !isNaN(parseFloat(propertyValue))) {
// set expression without quotes surrounding propertyValue
expression = propertyName + '=' + propertyValue;
}
// if the field is a html select element
if (fieldType === 'select') {
// propertyValue will be blank because select elements don't have a value attribute
// instead, we need to use the value of the child option element that is selected
propertyValue = $(element.html()).filter(":selected").val();
// set expression to assume propertyValue is a string value
expression = propertyName + '=\'' + ( !!propertyValue ? propertyValue : '' ) + '\'';
}
// if the input field type is a radio button but its not checked (selected)
if (fieldType === 'radio' && !element.is(':checked')) {
// we need to reset the expression so a blank value is used
// doing this means that only the checked/selected radio button values get set on the model
expression = propertyName + '=\'\'';
}
// evaluate the expression, just as angular's ngInit does
scope.$eval(expression);
}
};
});
(it looks more complex than it actual is because I've left the comments in - strip those out and there's really nothing to it)
To use it, each field that I am using ng-model on, I also need to use the attribute data-lv-initialize-value-on-scope. You don't need to pass any value on the attribute, the directive gets everything it needs from the element and attr parameters
So far it caters with text, number, radio and select fields. The pages I'm working on don't have any checkboxes, but as and when I come across those I dare say I'll need to add some code for those.
It works, and I think I prefer this to using ng-init with a load of server-side to determine whether to set a value, what its data type should be, etc
The only downside I can see at the moment is that processing a radio button set might be inefficient. IE. if you have 10 radio buttons, each marked up with ng-model and data-lv-initialize-value-on-scope; all 10 will run the data-lv-initialize-value-on-scope directive and set a value on the scope. At least 9 of the iterations will set a blank value on the scope, and at most only 1 will set the actual value on the scope.
Hey-ho, it seems to work for now :). Hope this helps someone in the future
Nathan

Dynamic default values for dynamically generated ng-model

I am facing problem in populating default values for dynamically generated form fields in using angular. So, I have a login form that generates itself based on the attribtes returned by aREST interface. Therefore for my html page, I just have :
<li ng-repeat="element in elements">
<label>UserName</label>
<input type="{{element.inputType}}" ng-model="{{element.fieldName[element]}}" required="required"/>
The default values are returned in an attribute called placehoder in elements object. following tag gives an idea of the task that I am trying to achieve
<input type="{{element.inputType}}" ng-model="{{element.fieldName[element]}}" required="required" placeholder="{{element.placeholder}}"/>
Finally, when the user clicks submit , I need to post the default value of text field if it has not been changed.
Any help would be highly appreciated.
Thanks
If you can add/use a library like underscorejs or lodash, then you can use their _.defaults() :
var object = { 'name': 'barney' };
_.defaults(object, { 'name': 'fred', 'employer': 'slate' });
// → { 'name': 'barney', 'employer': 'slate' }
with angular only, you could add a directive to your form, that watches 'submit' and sets the default values for you.
Thanks for replying #nilsK, I am very new to javascript frameworks and Angular is the first one that I am having my hand on.
So in my R&D with it , I solved my issue by adding the two arrays of values i.e. FieldName and Placeholder to the scope object that I use to post data to my backend. I assign values to these arrays from the objects(placeholder and fieldName) that recieve from REST service as:
$scope.user={};
$scope.user.FieldNames=[];
$scope.user.FieldValues=[];
angular.forEach($scope.elements,function(value,index){
$scope.user.fieldValues[index] = $scope.elements[index].placeholder;
$scope.user.fieldNames[index] = $scope.elements[index].fieldName;
})
and on the html form, I bind ng-model to the scope array of values that I want to display as defaults in text field.
<input type="{{element.inputType}}" ng-model="user.fieldValues[$index]" required="required" />
Therefore, the default values are posted if user does not change them and if there is a change, updated values are posted.
Any suggestions to improve this solution are most welcome.

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