在角佔位符NG選項

Question

我有一個選擇框，非常基本的，下面

<div ng-if="field.field_type == 'select'"> 
<p><strong>{{field.field_name}}:</strong></p> 
<div class="form_field"><label class="fontawesome-pencil" for="login_Custom"></label> 
<div class="input-group col-xs-8"> 
<style media="screen"> 
    select:not([multiple]) { 
     -webkit-appearance: none; 
     -moz-appearance: none; 
     background-position: right 50%; 
     background-repeat: no-repeat; 
     background-image: url(data:image/png;base64,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); 
     padding: .5em; 
     padding-right: 1.5em; 
    } 
</style> 
<select class="selectpicker form-control" default-option="Test" name="cusdropdown" ng-model="testInfo" ng-options="i.val as (i.nam) for i in field.options" style="width:450px"></select> <span class="input-group-addon buttonlike" ng-click="removeRegistrationfield($index)"><i class="fa fa-trash"></i></span></div> 
</div> 
</div> 

我想了field.field_name作爲佔位所示，我知道如何做到這一點的HTML，這是這個樣子

<select> 
    <option value="" disabled selected hidden>Please Choose</option> 
    <option value="0">Open when powered (most valves do this)</option> 
    <option value="1">Closed when powered, auto-opens when power is cut</option> 
</select> 

但是我怎麼能做到這一點內角？

感謝

Answer 1

您可以使用ng-options，並添加自己在同一時間的佔位符。

重複：<select> placeholder with angular/bootstrap not working