使用JavaScript将其他值设为默认值

Question

我试图使默认值不同于HTML中定义的值。 我无法更改HTML，因为它已由我们的母公司锁定。 但是，如果使用javascript，我可以更改默认值。 这是HTML

<div class="col-md-6">
      <div id="addressTypeWrapper" class="form-group">
        <label for="addressListArray[0].addressTypeString">Type</label>
        <select name="addressListArray[0].addressTypeString" id="addressListArray[0].addressTypeString" class="form-control" required >          
     <option value="Home" selected="selected">Home</option>
     <option value="Office">Office</option>
     <option value="Contact">Contact</option>
     <option value="Other">Other</option>
     <option value="Billing">Billing</option>
     <option value="Purchaser">Purchaser</option>
     <option value="Foreign">Foreign</option>
     <option value="Agency">Agency</option>
     <option value="Summer">Summer</option>
     <option value="School">School</option>
     <option value="Campus">Campus</option>
     <option value="Temporary">Temporary</option>
     <option value="Shipping">Shipping</option>
     <option value="Local">Local</option>
     <option value="Permanent">Permanent</option></select>
      </div>
    </div>

现在如何仅使用JavaScript将Office值设为默认值？

Answer 1

只需使用下面的那一行JavaScript来更改运行时的值

 document.getElementById('addressListArray[0].addressTypeString').value = 'Office'; 

 <div class="col-md-6"> <div id="addressTypeWrapper" class="form-group"> <label for="addressListArray[0].addressTypeString">Type</label> <select name="addressListArray[0].addressTypeString" id="addressListArray[0].addressTypeString" class="form-control" required > <option value="Home" selected="selected">Home</option> <option value="Office">Office</option> <option value="Contact">Contact</option> <option value="Other">Other</option> <option value="Billing">Billing</option> <option value="Purchaser">Purchaser</option> <option value="Foreign">Foreign</option> <option value="Agency">Agency</option> <option value="Summer">Summer</option> <option value="School">School</option> <option value="Campus">Campus</option> <option value="Temporary">Temporary</option> <option value="Shipping">Shipping</option> <option value="Local">Local</option> <option value="Permanent">Permanent</option></select> </div> </div> 

Answer 2

 !function(){var e=document.getElementsByTagName("option");e[0].selected=!1,e[1].selected=!0}(); 

 <div class="col-md-6"> <div id="addressTypeWrapper" class="form-group"> <label for="addressListArray[0].addressTypeString">Type</label> <select name="addressListArray[0].addressTypeString" id="addressListArray[0].addressTypeString" class="form-control" required> <option value="Home" selected="selected">Home</option> <option value="Office">Office</option> <option value="Contact">Contact</option> <option value="Other">Other</option> <option value="Billing">Billing</option> <option value="Purchaser">Purchaser</option> <option value="Foreign">Foreign</option> <option value="Agency">Agency</option> <option value="Summer">Summer</option> <option value="School">School</option> <option value="Campus">Campus</option> <option value="Temporary">Temporary</option> <option value="Shipping">Shipping</option> <option value="Local">Local</option> <option value="Permanent">Permanent</option> </select> </div> </div> 

Answer 3

选择下拉列表并使用.val() 。 如果它是动态id则添加另一个属性，例如data-dropdown="list" ，如下所示

$("select[data-dropdown='list']").val('Office');