I'm trying to add a validation field to one of my inputs, it should request the server whether the inputted VAT number is valid, so I'm using an async validator for this. Works fine with this code:
myApp.factory('isValidVat', function($q, $http) {
return function(vat) {
var deferred = $q.defer();
console.log(vat);
$http.get('/api/vat/' + vat).then(function() {
deferred.resolve();
}, function() {
deferred.reject();
});
return deferred.promise;
}
});
myApp.directive('validVat', function(isValidVat) {
return {
restrict: 'A',
require: 'ngModel',
link: function(scope, element, attrs, ngModel) {
ngModel.$asyncValidators.vat = isValidVat;
}
};
});
<form name="form" novalidate ng-submit="check(form)">
<div class="vat-field">
<label>VAT number
<input type="text" ng-model="formModel.vat" name="vat" valid-vat="true">
</label>
<div ng-show="registerForm.$submitted || registerForm.vat.$touched">
<span ng-show="registerForm.vat.$error.vat">
<small class="error">Your VAT address is not valid, please correct.</small>
</span>
</div>
</div>
<div class="country-field">
<label>Country
<select ng-model="formModel.country" name="country">
<option value="{{country.iso_3}}" ng-repeat="country in countries()">{{country.name}}</option>
</select>
</label>
</div>
<button type="submit">Check</button>
</form>
However, I want to make this asyncValidator check conditional on the value of another field (country, more specifically whether the country is a EU country).
The country field is a combobox, populoated via a service which has a record of all countries and their vat information and eu status.
However, I do not know how to inject the value of the selected country into the factory function. One idea was to link the selected country to it's own service and use it from the factory, but then the validation doesn't run again when another country is selected. If a non-EU country is selected, I don't really care what is in the field.
Pasing value into derective is easy, you can pass it to same attribute or some other. Its better not to use isolated scope, because attribute directive should be able to work on every element. So You can pass your country information to the validation directive, and then pass it to function which is returned by factory.
The other thing is dependency. Validation is only run when model itself is changed. So you have to place watch / observation on it.
Stop talking ... its code time ...
Here is fully working example based on your code :
http://jsbin.com/yuqibajehe/edit?html,js,output
.factory('isValidVat', function($q, $http, $timeout) {
return function(vat, country) {
var deferred = $q.defer();
console.log(vat, country);
$timeout(function() {
if (vat === country) {
deferred.resolve();
}
deferred.reject();
},1000);
return deferred.promise;
};
})
.directive('validVat', function(isValidVat) {
return {
restrict: 'A',
require: 'ngModel',
link: function(scope, element, attrs, ngModel) {
attrs.$observe('validVat', function() {
ngModel.$validate();
});
ngModel.$asyncValidators.vat = function(vat) {
return isValidVat(vat, attrs.validVat);
};
}
};
});
Ass you can see I have little bit simplified the async validator, but enough for now. function has two arguments, so I call it from other function.
Directive is used like that:
<input type="text" ng-model="vm.vat" name="vat" valid-vat="{{formModel.country}}" />
So we pass the value of model straight to the attribute valid-vat.
In directive we can then send the value into validator.
Then we have to observe the content of validator and run validation if this is changed using $validate().
For this case it is probably enough, but if you want to pass model directly like: valid-vat="formModel.country" it wouldn't work, because value of attribute doesn't change. So you would have go to the scope, or better evaluate attr value and watch its changes - like in this example: http://plnkr.co/edit/296x2shAVSe7FRv3mJnp?p=preview
I have a form with few fields, however a select and an input field are coupled: the validation on the input depends on which value the user chooses in the select field.
I'll try to clarify with an example. Let's say that the select contains names of planets:
<select id="planet" class="form-control" name="planet" ng-model="planet" ng-options="c.val as c.label for c in planets"></select>
in the input I apply custom validation via a custom directive named "input-validation":
<input id="city" input-validation iv-allow-if="planet==='earth'" class="form-control" name="city" ng-model="city" required>
where this is the directive:
.directive('inputValidation', [function() {
return {
require: 'ngModel',
restrict: 'A',
scope: {
ivAllowIf: '='
},
link: function(scope, elm, attrs, ctrl) {
ctrl.$parsers.unshift(function(viewValue) {
//input is allowed if the attribute is not present or the expression evaluates to true
var inputAllowed = attrs.ivAllowIf === undefined || scope.$parent.$eval(attrs.ivAllowIf);
if (inputAllowed) {
ctrl.$setValidity('iv', true);
return viewValue;
} else {
ctrl.$setValidity('iv', false);
return undefined;
}
});
}
};
}])
The full example can be examined in Plnkr: http://plnkr.co/edit/t2xMPy1ehVFA5KNEDfrf?p=preview
Whenever the select is modified, I need the input to be verified again. This is not happening in my code. What am I doing wrong?
I have done the same thing for validation of start-date on change of end-date. In the directive of start-date add watch for change of end-date and then call ngModel.$validate() in case end-date new value is defined.
scope.$watch(function () {
return $parse(attrs.endDate)(scope);
}, function () {
ngModel.$validate();
});
The important part to take is call to ngModel.$validate() inside the directive.
Note
you should use $validators for custom validations above to work. read here, $parsers is the old way - from angularjs 1.3 use $validators
FIXED PLUNKER LINK
I have the following ngRepeat code:
<div ng-repeat="drug in drugs | orderBy:'drugName'">
<input id="{{drug.drugName}}"
class="drugCheckbox"
name="{{drug.drugName}}"
type="checkbox" value="{{drug.drugName}}"
ng-model="foobar"
validate-foo
/>
{{drug.drugName}}
<!-- this is the error message, one per each repeat element -->
<span style="color:red" ng-show="myForm.{{drug.drugName}}.$error.summary">
Fill in the summary
</span>
<input type="text"
name="summary-{{drug.drugName}}"
id="summary-{{drug.drugName}}"
placeholder="Summary"/>
</div>
My validateFoo directive:
app.directive('validateFoo', function(){
return{
restrict: 'A',
require: 'ngModel',
link: function(scope, elem, attr, ctrl) {
ctrl.$parsers.unshift(function (viewValue) {
var id= attr.id;
//if the checkbox is checked, see if the text field has been filled in
if(viewValue) {
var val= document.getElementById('summary-' + id).value;
if(val.length == 0) {
ctrl.$setValidity("summary", false);
return undefined;
}
else {
ctrl.$setValidity(id, true);
return viewValue;
}
}
});
}
}
});
I cannot get the validation to work for any of the checkboxes, I am not clear on what to use for "ng-show" in the error message span element.
First of all that's because all fields will be registered in your formController under name {{drug.drugName}}.
Second thing is that there is no myForm.{{drug.drugName}}.$invalid in scope. You probably tried to do myForm[drug.drugName].$invalid. But it will not work anyway - look at 1.
I think that there still is no proper way to set name field dynamically in ng-repeat. Instead you need to create tour own directive, that will build repeated list elements as String, then append it to your HTML and $compile it place.
EDIT
I have developed one solution:
http://jsfiddle.net/ulfryk/gejfeLp7/
EDIT 2:
I've developed even simpler solution ( http://jsfiddle.net/ulfryk/5wq7539r/ ):
app.directive('fixRepeatedModelName', function () {
return {
link: function (scope, element, attrs, ngModelCtrl) {
if (!attrs.name) return;
ngModelCtrl.$name = attrs.name;
},
priority: '-100',
require: 'ngModel'
};
});
And add fix-repeated-model-name attribute to any ng-model with dynamic ({{ }} dependent) name placed inside ng-repeat. And it now works :)
So, the current code looks like this:
<input ng-pattern="validRegEx()" required>
$scope.validRegEx = function() {
// blah blah return regex
};
When I change an input on the form, I change the regex. The problem is data that was valid before (which should NOT be valid with the new RegEx) is still valid. How can I force the form to apply a regex to this field again, as opposed to just waiting for the user to blur the field again?
You could do it with a directive by watching for when the regex changes (or the conditions for it) and when it does you can re-run the validation by re-setting the value of the element.
something like this
angular.module('youappname', [])
.directive('reApply', function () {
return {
require: 'ngModel',
restrict: 'A',
link: function (scope, elm, attrs, ctrl) {
// you should change 'regex' in the following line to match the variable that when altered causes the regex to change..
scope.$watch('regex', function (value) {
if (ctrl.$viewValue !== ''){
ctrl.$setViewValue( ctrl.$viewValue );
}
});
}
};
});
and adding re-apply to your element
<input type="text" ng-pattern="validate()" re-apply="" name="userName" ng-model="user.name" required> <span class="error" ng-show="myForm.userName.$error.required">
demo at http://jsfiddle.net/Dztev/5/
This could also be done directly in the controller. This will watch the input stuff.name and if it changes, it will clear the scope.stuff.results field.
$scope.$watch("stuff.name", function(newValue, oldValue){
if(newValue != oldValue)
$scope.stuff.results = "";
});
I have a form with input fields and validation setup by adding the required attributes and such. But for some fields I need to do some extra validation. How would I "tap in" to the validation that FormController controls?
Custom validation could be something like "if these 3 fields are filled in, then this field is required and needs to be formatted in a particular way".
There's a method in FormController.$setValidity but that doesn't look like a public API so I rather not use it. Creating a custom directive and using NgModelController looks like another option, but would basically require me to create a directive for each custom validation rule, which I do not want.
Actually, marking a field from the controller as invalid (while also keeping FormController in sync) might be the thing that I need in the simplest scenario to get the job done, but I don't know how to do that.
Edit: added information about ngMessages (>= 1.3.X) below.
Standard form validation messages (1.0.X and above)
Since this is one of the top results if you Google "Angular Form Validation", currently, I want to add another answer to this for anyone coming in from there.
There's a method in FormController.$setValidity but that doesn't look like a public API so I rather not use it.
It's "public", no worries. Use it. That's what it's for. If it weren't meant to be used, the Angular devs would have privatized it in a closure.
To do custom validation, if you don't want to use Angular-UI as the other answer suggested, you can simply roll your own validation directive.
app.directive('blacklist', function (){
return {
require: 'ngModel',
link: function(scope, elem, attr, ngModel) {
var blacklist = attr.blacklist.split(',');
//For DOM -> model validation
ngModel.$parsers.unshift(function(value) {
var valid = blacklist.indexOf(value) === -1;
ngModel.$setValidity('blacklist', valid);
return valid ? value : undefined;
});
//For model -> DOM validation
ngModel.$formatters.unshift(function(value) {
ngModel.$setValidity('blacklist', blacklist.indexOf(value) === -1);
return value;
});
}
};
});
And here's some example usage:
<form name="myForm" ng-submit="doSomething()">
<input type="text" name="fruitName" ng-model="data.fruitName" blacklist="coconuts,bananas,pears" required/>
<span ng-show="myForm.fruitName.$error.blacklist">
The phrase "{{data.fruitName}}" is blacklisted</span>
<span ng-show="myForm.fruitName.$error.required">required</span>
<button type="submit" ng-disabled="myForm.$invalid">Submit</button>
</form>
Note: in 1.2.X it's probably preferrable to substitute ng-if for ng-show above
Here is an obligatory plunker link
Also, I've written a few blog entries about just this subject that goes into a little more detail:
Angular Form Validation
Custom Validation Directives
Edit: using ngMessages in 1.3.X
You can now use the ngMessages module instead of ngShow to show your error messages. It will actually work with anything, it doesn't have to be an error message, but here's the basics:
Include <script src="angular-messages.js"></script>
Reference ngMessages in your module declaration:
var app = angular.module('myApp', ['ngMessages']);
Add the appropriate markup:
<form name="personForm">
<input type="email" name="email" ng-model="person.email" required/>
<div ng-messages="personForm.email.$error">
<div ng-message="required">required</div>
<div ng-message="email">invalid email</div>
</div>
</form>
In the above markup, ng-message="personForm.email.$error" basically specifies a context for the ng-message child directives. Then ng-message="required" and ng-message="email" specify properties on that context to watch. Most importantly, they also specify an order to check them in. The first one it finds in the list that is "truthy" wins, and it will show that message and none of the others.
And a plunker for the ngMessages example
Angular-UI's project includes a ui-validate directive, which will probably help you with this. It let's you specify a function to call to do the validation.
Have a look at the demo page: http://angular-ui.github.com/, search down to the Validate heading.
From the demo page:
<input ng-model="email" ui-validate='{blacklist : notBlackListed}'>
<span ng-show='form.email.$error.blacklist'>This e-mail is black-listed!</span>
then in your controller:
function ValidateCtrl($scope) {
$scope.blackList = ['bad#domain.example','verybad#domain.example'];
$scope.notBlackListed = function(value) {
return $scope.blackList.indexOf(value) === -1;
};
}
You can use ng-required for your validation scenario ("if these 3 fields are filled in, then this field is required":
<div ng-app>
<input type="text" ng-model="field1" placeholder="Field1">
<input type="text" ng-model="field2" placeholder="Field2">
<input type="text" ng-model="field3" placeholder="Field3">
<input type="text" ng-model="dependentField" placeholder="Custom validation"
ng-required="field1 && field2 && field3">
</div>
You can use Angular-Validator.
Example: using a function to validate a field
<input type = "text"
name = "firstName"
ng-model = "person.firstName"
validator = "myCustomValidationFunction(form.firstName)">
Then in your controller you would have something like
$scope.myCustomValidationFunction = function(firstName){
if ( firstName === "John") {
return true;
}
You can also do something like this:
<input type = "text"
name = "firstName"
ng-model = "person.firstName"
validator = "'!(field1 && field2 && field3)'"
invalid-message = "'This field is required'">
(where field1 field2, and field3 are scope variables. You might also want to check if the fields do not equal the empty string)
If the field does not pass the validator then the field will be marked as invalid and the user will not be able to submit the form.
For more use cases and examples see: https://github.com/turinggroup/angular-validator
Disclaimer: I am the author of Angular-Validator
I recently created a directive to allow for expression-based invalidation of angular form inputs. Any valid angular expression can be used, and it supports custom validation keys using object notation. Tested with angular v1.3.8
.directive('invalidIf', [function () {
return {
require: 'ngModel',
link: function (scope, elm, attrs, ctrl) {
var argsObject = scope.$eval(attrs.invalidIf);
if (!angular.isObject(argsObject)) {
argsObject = { invalidIf: attrs.invalidIf };
}
for (var validationKey in argsObject) {
scope.$watch(argsObject[validationKey], function (newVal) {
ctrl.$setValidity(validationKey, !newVal);
});
}
}
};
}]);
You can use it like this:
<input ng-model="foo" invalid-if="{fooIsGreaterThanBar: 'foo > bar',
fooEqualsSomeFuncResult: 'foo == someFuncResult()'}/>
Or by just passing in an expression (it will be given the default validationKey of "invalidIf")
<input ng-model="foo" invalid-if="foo > bar"/>
Here's a cool way to do custom wildcard expression validations in a form (from: Advanced form validation with AngularJS and filters):
<form novalidate="">
<input type="text" id="name" name="name" ng-model="newPerson.name"
ensure-expression="(persons | filter:{name: newPerson.name}:true).length !== 1">
<!-- or in your case:-->
<input type="text" id="fruitName" name="fruitName" ng-model="data.fruitName"
ensure-expression="(blacklist | filter:{fruitName: data.fruitName}:true).length !== 1">
</form>
app.directive('ensureExpression', ['$http', '$parse', function($http, $parse) {
return {
require: 'ngModel',
link: function(scope, ele, attrs, ngModelController) {
scope.$watch(attrs.ngModel, function(value) {
var booleanResult = $parse(attrs.ensureExpression)(scope);
ngModelController.$setValidity('expression', booleanResult);
});
}
};
}]);
jsFiddle demo (supports expression naming and multiple expressions)
It's similar to ui-validate, but you don't need a scope specific validation function (this works generically) and ofcourse you don't need ui.utils this way.
#synergetic I think #blesh suppose to put function validate as below
function validate(value) {
var valid = blacklist.indexOf(value) === -1;
ngModel.$setValidity('blacklist', valid);
return valid ? value : undefined;
}
ngModel.$formatters.unshift(validate);
ngModel.$parsers.unshift(validate);
Update:
Improved and simplified version of previous directive (one instead of two) with same functionality:
.directive('myTestExpression', ['$parse', function ($parse) {
return {
restrict: 'A',
require: 'ngModel',
link: function (scope, element, attrs, ctrl) {
var expr = attrs.myTestExpression;
var watches = attrs.myTestExpressionWatch;
ctrl.$validators.mytestexpression = function (modelValue, viewValue) {
return expr == undefined || (angular.isString(expr) && expr.length < 1) || $parse(expr)(scope, { $model: modelValue, $view: viewValue }) === true;
};
if (angular.isString(watches)) {
angular.forEach(watches.split(",").filter(function (n) { return !!n; }), function (n) {
scope.$watch(n, function () {
ctrl.$validate();
});
});
}
}
};
}])
Example usage:
<input ng-model="price1"
my-test-expression="$model > 0"
my-test-expression-watch="price2,someOtherWatchedPrice" />
<input ng-model="price2"
my-test-expression="$model > 10"
my-test-expression-watch="price1"
required />
Result: Mutually dependent test expressions where validators are executed on change of other's directive model and current model.
Test expression has local $model variable which you should use to compare it to other variables.
Previously:
I've made an attempt to improve #Plantface code by adding extra directive. This extra directive very useful if our expression needs to be executed when changes are made in more than one ngModel variables.
.directive('ensureExpression', ['$parse', function($parse) {
return {
restrict: 'A',
require: 'ngModel',
controller: function () { },
scope: true,
link: function (scope, element, attrs, ngModelCtrl) {
scope.validate = function () {
var booleanResult = $parse(attrs.ensureExpression)(scope);
ngModelCtrl.$setValidity('expression', booleanResult);
};
scope.$watch(attrs.ngModel, function(value) {
scope.validate();
});
}
};
}])
.directive('ensureWatch', ['$parse', function ($parse) {
return {
restrict: 'A',
require: 'ensureExpression',
link: function (scope, element, attrs, ctrl) {
angular.forEach(attrs.ensureWatch.split(",").filter(function (n) { return !!n; }), function (n) {
scope.$watch(n, function () {
scope.validate();
});
});
}
};
}])
Example how to use it to make cross validated fields:
<input name="price1"
ng-model="price1"
ensure-expression="price1 > price2"
ensure-watch="price2" />
<input name="price2"
ng-model="price2"
ensure-expression="price2 > price3"
ensure-watch="price3" />
<input name="price3"
ng-model="price3"
ensure-expression="price3 > price1 && price3 > price2"
ensure-watch="price1,price2" />
ensure-expression is executed to validate model when ng-model or any of ensure-watch variables is changed.
Custom Validations that call a Server
Use the ngModelController $asyncValidators API which handles asynchronous validation, such as making an $http request to the backend. Functions added to the object must return a promise that must be resolved when valid or rejected when invalid. In-progress async validations are stored by key in ngModelController.$pending. For more information, see AngularJS Developer Guide - Forms (Custom Validation).
ngModel.$asyncValidators.uniqueUsername = function(modelValue, viewValue) {
var value = modelValue || viewValue;
// Lookup user by username
return $http.get('/api/users/' + value).
then(function resolved() {
//username exists, this means validation fails
return $q.reject('exists');
}, function rejected() {
//username does not exist, therefore this validation passes
return true;
});
};
For more information, see
ngModelController $asyncValidators API
AngularJS Developer Guide - Forms (Custom Validation).
Using the $validators API
The accepted answer uses the $parsers and $formatters pipelines to add a custom synchronous validator. AngularJS 1.3+ added a $validators API so there is no need to put validators in the $parsers and $formatters pipelines:
app.directive('blacklist', function (){
return {
require: 'ngModel',
link: function(scope, elem, attr, ngModel) {
ngModel.$validators.blacklist = function(modelValue, viewValue) {
var blacklist = attr.blacklist.split(',');
var value = modelValue || viewValue;
var valid = blacklist.indexOf(value) === -1;
return valid;
});
}
};
});
For more information, see AngularJS ngModelController API Reference - $validators.
In AngularJS the best place to define Custom Validation is Cutsom directive.
AngularJS provide a ngMessages module.
ngMessages is a directive that is designed to show and hide messages
based on the state of a key/value object that it listens on. The
directive itself complements error message reporting with the ngModel
$error object (which stores a key/value state of validation errors).
For custom form validation One should use ngMessages Modules with custom directive.Here i have a simple validation which will check if number length is less then 6 display an error on screen
<form name="myform" novalidate>
<table>
<tr>
<td><input name='test' type='text' required ng-model='test' custom-validation></td>
<td ng-messages="myform.test.$error"><span ng-message="invalidshrt">Too Short</span></td>
</tr>
</table>
</form>
Here is how to create custom validation directive
angular.module('myApp',['ngMessages']);
angular.module('myApp',['ngMessages']).directive('customValidation',function(){
return{
restrict:'A',
require: 'ngModel',
link:function (scope, element, attr, ctrl) {// 4th argument contain model information
function validationError(value) // you can use any function and parameter name
{
if (value.length > 6) // if model length is greater then 6 it is valide state
{
ctrl.$setValidity('invalidshrt',true);
}
else
{
ctrl.$setValidity('invalidshrt',false) //if less then 6 is invalide
}
return value; //return to display error
}
ctrl.$parsers.push(validationError); //parsers change how view values will be saved in the model
}
};
});
$setValidity is inbuilt function to set model state to valid/invalid
I extended #Ben Lesh's answer with an ability to specify whether the validation is case sensitive or not (default)
use:
<input type="text" name="fruitName" ng-model="data.fruitName" blacklist="Coconuts,Bananas,Pears" caseSensitive="true" required/>
code:
angular.module('crm.directives', []).
directive('blacklist', [
function () {
return {
restrict: 'A',
require: 'ngModel',
scope: {
'blacklist': '=',
},
link: function ($scope, $elem, $attrs, modelCtrl) {
var check = function (value) {
if (!$attrs.casesensitive) {
value = (value && value.toUpperCase) ? value.toUpperCase() : value;
$scope.blacklist = _.map($scope.blacklist, function (item) {
return (item.toUpperCase) ? item.toUpperCase() : item
})
}
return !_.isArray($scope.blacklist) || $scope.blacklist.indexOf(value) === -1;
}
//For DOM -> model validation
modelCtrl.$parsers.unshift(function (value) {
var valid = check(value);
modelCtrl.$setValidity('blacklist', valid);
return value;
});
//For model -> DOM validation
modelCtrl.$formatters.unshift(function (value) {
modelCtrl.$setValidity('blacklist', check(value));
return value;
});
}
};
}
]);
Some great examples and libs presented in this thread, but they didn't quite have what I was looking for. My approach: angular-validity -- a promise based validation lib for asynchronous validation, with optional Bootstrap styling baked-in.
An angular-validity solution for the OP's use case might look something like this:
<input type="text" name="field4" ng-model="field4"
validity="eval"
validity-eval="!(field1 && field2 && field3 && !field4)"
validity-message-eval="This field is required">
Here's a Fiddle, if you want to take it for a spin. The lib is available on GitHub, has detailed documentation, and plenty of live demos.