AngularJS ngForm与ngRepeat中的ngIf绑定会导致形式不确定

时间:2015-12-02 19:37:23

标签: javascript angularjs angularjs-ng-form

ngForm - 嵌套在ngRepeat中。表单绑定到页面控制器上的变量。然后使用ngIf基于选项卡的活动索引将表单添加到DOM或从DOM中删除。

奇怪的是,如果我按升序激活制表符,表单将正确绑定到控制器的表单变量,但如果我按降序激活制表符,则表单不受约束。



angular.module("myApp", [])

.controller("MyController", function($scope) {
  var ctrl = this;

  ctrl.index = 0;
  ctrl.tabs = [1, 2, 3, 4, 5];
  ctrl.text = null;

  ctrl.setIndex = function(index) {
    ctrl.index = index;
  };
});

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.3/angular.min.js"></script>

<body ng-app="myApp">
  <div ng-controller="MyController as ctrl">
    {{ctrl.form ? "Form is bound!" : "Form is NOT bound." }}
    <div ng-repeat="item in ctrl.tabs">
      <ng-form name="ctrl.form" ng-if="ctrl.index===$index">
        <input type="text" ng-attr-name="{{item+'-test'}}" ng-model="ctrl.text" required/>
      </ng-form>
    </div>
    <ul>
      <li><a href="#" ng-click="ctrl.setIndex(0)">1</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(1)">2</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(2)">3</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(3)">4</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(4)">5</a></li>
    </ul>
  </div>
</body>
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任何人都知道为什么会这样?

1 个答案:

答案 0 :(得分:1)

我不知道为什么表单是从控制器解除绑定的(这必须归因于ng-repeat内部)。

但是,如果将每个表单绑定到不同的名称,即:

<ng-form name="ctrl.form{{item}}" ng-if="ctrl.index===$index">

并定义一个访问它的简单方法:

ctrl.currentForm = function() {
   return ctrl['form' + ctrl.tabs[ctrl.index]];
};

然后一切都按预期工作。

angular.module("myApp", [])

.controller("MyController", function($scope) {
  var ctrl = this;

  ctrl.index = 0;
  ctrl.tabs = [1, 2, 3, 4, 5];
  ctrl.text = null;

  ctrl.currentForm = function() {
     return ctrl['form' + ctrl.tabs[ctrl.index]];
  };
  
  ctrl.setIndex = function(index) {
    ctrl.index = index;
  };
});
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.3/angular.min.js"></script>

<body ng-app="myApp">
  <div ng-controller="MyController as ctrl">
    {{ctrl.currentForm() ? "Form is bound in tab with index " + ctrl.index + "!" : "Form is NOT bound." }}
    <div ng-repeat="item in ctrl.tabs">
      <ng-form name="ctrl.form{{item}}" ng-if="ctrl.index===$index">
        <input type="text" ng-attr-name="{{item+'-test'}}" ng-model="ctrl.text" required/>
      </ng-form>
    </div>
    <ul>
      <li><a href="#" ng-click="ctrl.setIndex(0)">1</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(1)">2</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(2)">3</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(3)">4</a></li>
      <li><a href="#" ng-click="ctrl.setIndex(4)">5</a></li>
    </ul>
  </div>
</body>