我已经搜索了谷歌,在这个上面什么也找不到。

我有这个代码。

<select ng-model="somethingHere" 
        ng-options="option.value as option.name for option in options"
></select>

有这样的数据

options = [{
   name: 'Something Cool',
   value: 'something-cool-value'
}, {
   name: 'Something Else',
   value: 'something-else-value'
}];

输出是这样的。

<select ng-model="somethingHere"  
        ng-options="option.value as option.name for option in options" 
        class="ng-pristine ng-valid">

    <option value="?" selected="selected"></option>
    <option value="0">Something Cool</option>
    <option value="1">Something Else</option>
</select>

如何将数据中的第一个选项设置为默认值,从而得到这样的结果呢?

<select ng-model="somethingHere" ....>
    <option value="0" selected="selected">Something Cool</option>
    <option value="1">Something Else</option>
</select>

当前回答

对于Ben Lesh的回答,应该有这样一条线

ng-init="somethingHere = somethingHere || options[0]" 

而不是

ng-init="somethingHere = somethingHere || options[0].value" 

也就是说,

<选择ng-model = " somethingHere " ng-init="somethingHere = somethingHere || options[0]" Ng-options ="option.name for options track by option.value"> < /选择>

其他回答

对于Ben Lesh的回答,应该有这样一条线

ng-init="somethingHere = somethingHere || options[0]" 

而不是

ng-init="somethingHere = somethingHere || options[0].value" 

也就是说,

<选择ng-model = " somethingHere " ng-init="somethingHere = somethingHere || options[0]" Ng-options ="option.name for options track by option.value"> < /选择>

Srivathsa Harish Venkataramana只有一个回答提到了轨道,这确实是一个解决方案!

下面是一个关于如何在select ng-options中使用track by的例子(链接如下):

<select ng-model="selectedCity"
        ng-options="city as city.name for city in cities track by city.id">
  <option value="">-- Select City --</option>
</select>

如果selectedCity定义在angular作用域上,并且它的id属性与cities列表中任何城市的id值相同,它将在加载时自动选择。

下面是普伦克的解释: http://plnkr.co/edit/1EVs7R20pCffewrG0EmI?p=preview

有关更多细节,请参阅源代码文档: https://code.angularjs.org/1.3.15/docs/api/ng/directive/select

如果你想确保你的$scope。当你的视图初始化时,somethingHere的值不会被覆盖,你会想要合并(somethingHere = somethingHere || options[0].value) ng-init中的值,如下所示:

<select ng-model="somethingHere" 
        ng-init="somethingHere = somethingHere || options[0].value"
        ng-options="option.value as option.name for option in options">
</select>

您可以像这样简单地使用ng-init

<select ng-init="somethingHere = options[0]" 
        ng-model="somethingHere" 
        ng-options="option.name for option in options">
</select>

我认为最简单的方法是

 ng-selected="$first"