动态添加角场验证

Question

I am trying to create form builder application in Angular.js and I got stuck on validating fields. Angular provides great validation but one thing is missing for my usecase, and that is turning various validation on / off dynamically. I want to let my user add new form fields and then specify a validation (Angular default minlength, maxlength, ...) for each field alone.

Lets say that I want to create a button, that will add / remove minlength validation on a specified field (fields are stored in my model and are displayed through custom form and field directives), how should I do this?

I created a simple Plunker - http://plnkr.co/edit/pCXgwgnNbZkcAcl263JN?p=preview can you tell me what shoud be inside the toggleValidation() function?

HTML

<div ng-class="{ 'has-error' : userForm.name.$invalid && !userForm.name.$pristine }" class="form-group">
          <label>Name</label>
          <input type="text" ng-model="user.name" class="form-control" name="name" />
          <p class="help-block" ng-show="userForm.name.$invalid && !userForm.name.$pristine">Validation error.</p>
        </div>
        <a href="" class="btn btn-success" ng-click="toggleValidation()">Toggle minlength validation</a>

JS

validationApp.controller('mainController', function($scope) {

    $scope.toggleValidation = function()
    {
      // ???
    }

});

Answer 1

You should consider using something like http://formly-js.github.io/angular-formly/#!/ to dynamically generate forms from a set of JSON objects. Then it would very very easy to toggle certain validation methods on and off.

Answer 2

I should try something like this:

validationApp.controller('mainController', function($scope) {

  $scope.toggleValidation = function(validationFlag) {
    $scope.validationIsOn = validationFlag;
  }

  $scope.minlengthValidation = function (field, minlen) {
    if ($scope.validationIsOn) {
      return (field.length >= minlen);
    } else {
      return true;
    }
  }

});

Note: this code is not real code, but it just wants to give an idea to build the real code...