我如何从数组中获取两个值并将它们包含在angularjs控制器中的新函数中

Question

I am new to web development (started with the MEAN stack) and I got stuck with this I suppose obvious answer, but I couldn't find a solution here yet so I thought I give it a shot.

What I would like to do in short is:

• Retrieve several Values from an Array
• Include those extracted values into a new scope
• Everything should happen in the controller, since I would like to post all values, including the new one in my database (mongo).

Ideally, I would retrieve the values and add them to the new value like so

index = value[0]*weight[0] + value[1]*weight[1].... and so forth 

I have the following code snippet inside my angular controller

 $scope.alerts = [
    { title: 'someTitle1',
      weighttitle: 'someweightTitle1',
      value: 1,
      weight: 30,
      options: {
        showTicks: true,
        hidePointerLabels: true,
        hideLimitLabels: true,
        stepsArray: [
            { value: 1, legend: 'Very poor' },
            { value: 2, legend: 'Very poor' },
            { value: 3, legend: 'Fair' },
            { value: 4, legend: 'Very poor' },
            { value: 5, legend: 'Average' }

        ]
      }
    },
    { title: 'someTitle2',
      weighttitle: 'someweightTitle2',
      value: 1,
      weight: 60,
      options: {
        showTicks: true,
        hidePointerLabels: true,
        hideLimitLabels: true,
        stepsArray: [
            { value: 1, legend: 'Very poor' },
            { value: 2, legend: 'Very poor' },
            { value: 3, legend: 'Fair' },
            { value: 4, legend: 'Very poor' },
            { value: 5, legend: 'Average' }

        ]
      }
    }
];

I thought the solution should somehow look like this

$scope.index = alert.value*alert.weight

but that did not quite make it. I am pretty clueless at this point how to retrieve those values. Maybe I have a misunderstanding of the underlying concept.

Grateful for any help!

The solutions did work, but they did not change dynamically. The HTML code for this problem looks like this:

<section ng-controller="ArticlesController">
  <div class="page-header">
    <h1>Neue Evaluierung</h1>
  </div>
  <div class="col-md-12">
    <form name="articleForm" class="form-horizontal" ng-submit="create(articleForm.$valid)" novalidate>
      <fieldset>

        <div class="row form-group">
         <h3>Projekttitel</h3><input type="submit" class="btn btn-default btn-lg btn-success">
        </div>
        <div ng-show="error" class="text-danger">
          <strong ng-bind="error"></strong>
        </div>

        <input name="title" type="text" ng-model="title" id="title" class="form-control">

        <div ng-repeat="alert in alerts">

          <h3>{{alert.someTitle}}</h3>
          <input type="number" ng-model="alert.value"/>

          <div>
            <rzslider rz-slider-model="alert.value"
                      rz-slider-options="alert.options"></rzslider>
          </div>

          <br>
          <br>
          <br>
          <br>

          <div>
            <h4>{{alert.someweightTitle}}</h4>
            <input type="number" ng-model="alert.weight"/>
            <div>
              <md-slider flex md-discrete ng-model="alert.weight" step="1" min="1" max="100" aria-label="rating"></md-slider>
            </div>
          </div>

          <input type="number" ng-model="index"/>
          <input type="number" ng-model="indexdynamic"/>

        </div>


      </fieldset>
    </form>
  </div>
</section>

Answer 1

You can use the reduce function like this:

 var alerts = [ { title: 'someTitle1', weighttitle: 'someweightTitle1', value: 1, weight: 30, options: { showTicks: true, hidePointerLabels: true, hideLimitLabels: true, stepsArray: [ { value: 1, legend: 'Very poor' }, { value: 2, legend: 'Very poor' }, { value: 3, legend: 'Fair' }, { value: 4, legend: 'Very poor' }, { value: 5, legend: 'Average' } ] } }, { title: 'someTitle2', weighttitle: 'someweightTitle2', value: 1, weight: 60, options: { showTicks: true, hidePointerLabels: true, hideLimitLabels: true, stepsArray: [ { value: 1, legend: 'Very poor' }, { value: 2, legend: 'Very poor' }, { value: 3, legend: 'Fair' }, { value: 4, legend: 'Very poor' }, { value: 5, legend: 'Average' } ] } } ]; var index = alerts.reduce(function(prev, next) { return prev + (next.value*next.weight); }, 0); console.log(index); // 90 

Of course you need to store the result in your scope. I just ignored the scope for the snippet since its not relevant to the reduce function.

Answer 2

UPDATE:

The code above show in ng-repeat your alerts array, with the calculated index . It also provide a form that can add an item to alerts array, and also calculted its index .

You can try it on this Fiddle .

---

HTML code

<section ng-controller="ArticlesController">
  <div class="col-md-12">
    <div ng-repeat="alert in alerts">
      <strong>{{alert.title}}</strong>: {{alert.value}}
      <br/>
      <strong>{{alert.weighttitle}}</strong>: {{alert.weight}}
      <br/>
      <strong>Index:</strong> {{alert.index}}<br/><br/>
    </div>
    <form>
      <h1>Add an alert</h1>
      Title:<input type="text" ng-model="new.title"/><br/>
      Value:<input type="text" ng-model="new.value"/><br/>
      Weight title:<input type="text" ng-model="new.weighttitle"/><br/>
      Weight:<input type="text" ng-model="new.weight"/><br/>
      Index: {{new.value * new.weight}}<br/>
      <button type="submit" ng-click="create()">Add this!</button>
    </form>
  </div>
</section>

---

AngularJS code

var myApp = angular.module('myApp', []);

function ArticlesController($scope) {
  $scope.new = {};

  $scope.alerts = [
      { title: 'someTitle1',
        weighttitle: 'someweightTitle1',
        value: 1,
        weight: 30,
        options: {
          showTicks: true,
          hidePointerLabels: true,
          hideLimitLabels: true,
          stepsArray: [
              { value: 1, legend: 'Very poor' },
              { value: 2, legend: 'Very poor' },
              { value: 3, legend: 'Fair' },
              { value: 4, legend: 'Very poor' },
              { value: 5, legend: 'Average' }

          ]
        }
      },
      { title: 'someTitle2',
        weighttitle: 'someweightTitle2',
        value: 1,
        weight: 60,
        options: {
          showTicks: true,
          hidePointerLabels: true,
          hideLimitLabels: true,
          stepsArray: [
              { value: 1, legend: 'Very poor' },
              { value: 2, legend: 'Very poor' },
              { value: 3, legend: 'Fair' },
              { value: 4, legend: 'Very poor' },
              { value: 5, legend: 'Average' }
          ]
        }
      }
  ];

  for(var i = 0; i < $scope.alerts.length; i++) {
    // Add value * weight to index
    $scope.alerts[i].index = $scope.alerts[i].value * $scope.alerts[i].weight;
  }

  $scope.create = function() {
      // Calculate index
      $scope.new.index = $scope.new.value * $scope.new.weight;
      // Add it to the array
      $scope.alerts.push(JSON.parse(JSON.stringify($scope.new)));
  }
}