JSFiddle - React, Tailwind, and code Playground
by marhaba
HTML
<body ng-app="demoApp">
<div ng-controller="DemoController">
<div>
<h2>Incorrect</h2>
<p>We might expect the select box to be initialized to "two," but it isn't because these are two different objects.</p>
<select ng-model="incorrectlySelected"
ng-options="opt for opt in options">
</select>
The value selected is {{ incorrectlySelected.value }}.
</div>
<div>
<h2>Correct</h2>
<p>Here we are referencing the same object in <code>$scope.correctlySelected</code> as in <code>$scope.options</code>, so the select box is initialized correctly.</p>
<select ng-model="correctlySelected"
ng-options="opt as opt.label for opt in options">
</select>
The value selected is {{ correctlySelected.value }}.
</div>
</div>
</body>
JavaScript
angular.module('demoApp', []).controller('DemoController', function($scope) {
$scope.options = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31];
// Although this object has the same properties as the one in $scope.options,
// Angular considers them different because it compares based on reference
$scope.incorrectlySelected = { label: 'two', value: 2 };
// Here we are referencing the same object, so Angular inits the select box correctly
$scope.correctlySelected = $scope.options[1];
});