无法绑定模型数组中的输入字段数据

Question

当我在输入字段中输入值时，我无法绑定模型数组中的值而无法在$scope.selectfield[$index]中访问。

以下是Html代码的一部分：

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＆＃13;

var ap = angular.module("myapp", []);
ap.controller("membercontroller", function($scope, $http, $window) {
  $scope.selectfield = [];

  $scope.dropdown = ["abc", "xyz", "pq", "aqz"];
})

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.0/angular.min.js"></script>
<div ng-app="myapp" ng-controller="membercontroller">
  <div class="col-lg-6">
    <label id="billamt"> Select Members:</label>
    <div class="dropdown">
    
      <button class="btn btn-default dropdown-toggle" type="checkbox" id="dropdownMenu1" data-toggle="dropdown" aria-haspopup="true" aria- expanded="true">
        Select members
        <span class="caret"></span>
      </button>
      
      <ul class="dropdown-menu" aria-labelledby="dropdownMenu1">
        <li ng-repeat="z in dropdown">
          <a href="#">
            {{z}}
            <br>
            <input type="number" ng-model="selectfield[$index]" value="{{selectfield[$index]}}"/>
          </a>
        </li>
      </ul>
      
    </div>
  </div>
</div>

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Answer 1

$ index未定义。尝试将'track by $ index'添加到ng-repeat。