Using JSON data to populate a select menu in AngularJS using the ng-options directive

Question

Using JSON data to populate a select menu in AngularJS using the ng-options directive

UPDATE: I have successfully resolved my issue. Thanks for the assistance, everyone.

I am working with an array of JSON objects that are structured like so:

[{"id":"id1", "text":"text1"}, {"id":"id2", "text":"text2"},....]

My goal is to populate an AngularJS select box using these objects, where the text values display in the dropdown and the id values are bound to the model. However, I am struggling to figure out the correct approach.

Currently, this is what my select code looks like, but it does not show anything:

<select name="field" ng-model="npe.formData.field" ng-options="field.id as field.text for field in fields">

If I use ng-options in a different way, I can get items to display, but the value binding to the model is incorrect:

ng-options="field as field.text for field in fields"

I have come across suggestions to use "(key, value)", but I am struggling to understand how it should be implemented.

javascript json angularjs

Answer 1

Answer №1

When iterating through a map, the key-value pair is necessary. In your scenario, you are actually looping through an array of objects. To demonstrate the use of key-value pairs:

$scope.map={item1:'a',item2:'b'};
...
<li ng-repeat="(id,text) in map">{{id}}) {{text}}</li>

This code would display "item1) a" and so forth.

As for the snippet you mentioned doesn't work:

ng-options="field.id as field.text for field in fields"

You can see it in action here - http://jsfiddle.net/7eqsc/2/. It functions smoothly and updates the model with the correct id.

<div ng-app="myApp">
<div ng-controller="myCtrl">

    <div ng-repeat="(id,text) in notes">{{text}}</div>
    <select ng-model="model.id" ng-options="note.id as note.text for note in notes" ></select>

    Selected id:{{model.id}}

</div>

Answer 2

When iterating through a map, the key-value pair is necessary. In your scenario, you are actually looping through an array of objects. To demonstrate the use of key-value pairs:

$scope.map={item1:'a',item2:'b'};
...
<li ng-repeat="(id,text) in map">{{id}}) {{text}}</li>

This code would display "item1) a" and so forth.

As for the snippet you mentioned doesn't work:

ng-options="field.id as field.text for field in fields"

You can see it in action here - http://jsfiddle.net/7eqsc/2/. It functions smoothly and updates the model with the correct id.

<div ng-app="myApp">
<div ng-controller="myCtrl">

    <div ng-repeat="(id,text) in notes">{{text}}</div>
    <select ng-model="model.id" ng-options="note.id as note.text for note in notes" ></select>

    Selected id:{{model.id}}

</div>

Answer 3

Answer №2

Check out this JSFiddle example, demonstrating a basic controller assigning values. If you're struggling with a similar issue, the absence of using ng-model may be causing it.

function TodoCtrl($scope) {
    $scope.fields = [{"id":"id1", "text":"text1"}, {"id":"id2", "text":"text2"}];
    $scope.choice = null;
}

Here's the HTML snippet:

<div ng-app>
  <div ng-controller="TodoCtrl">
      <h2>Chosen = {{ choice }}</h2>
      <select ng-options="field.id as field.text for field in fields" ng-model="choice"></select>
  </div>
</div>

The key takeaway is that ng-options relies on having ng-model to function properly, otherwise it won't have any effect.

Answer 4

Check out this JSFiddle example, demonstrating a basic controller assigning values. If you're struggling with a similar issue, the absence of using ng-model may be causing it.

function TodoCtrl($scope) {
    $scope.fields = [{"id":"id1", "text":"text1"}, {"id":"id2", "text":"text2"}];
    $scope.choice = null;
}

Here's the HTML snippet:

<div ng-app>
  <div ng-controller="TodoCtrl">
      <h2>Chosen = {{ choice }}</h2>
      <select ng-options="field.id as field.text for field in fields" ng-model="choice"></select>
  </div>
</div>

The key takeaway is that ng-options relies on having ng-model to function properly, otherwise it won't have any effect.

Using JSON data to populate a select menu in AngularJS using the ng-options directive

Answer №1

Answer №2

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