Ng-options with index默认包含一个空值

Question

我试图使用ng-options(以索引为值)创建默认选择第一个元素的下拉菜单。我试着在控制器中设置模型，但没有帮助。

function MyCtrl($scope) {
    $scope.model = 0;
    $scope.years = [2012, 2013, 2014];
}
<div ng-controller="MyCtrl">
  <select ng-model="model" ng-options="idx as year for (idx, year) in years"></select>
    <p ng-bind="model"></p>
</div>

https://jsfiddle.net/kxugpwxk/

我做错了什么?为什么在下拉菜单的顶部选择了一个空白值?

Answer 1

您可以在ng-options调用中使用indexOf

<div ng-controller="MyCtrl">
  <select ng-model="model" ng-options="years.indexOf(year) as year for year in years"></select>
  <p ng-bind="model"></p>
</div>

Answer 2

try this:

<select ng-options="idx as year for (idx, year) in years" ng-model="model"  ng-init="model = years[0]"></select>