本文翻译自：Combating AngularJS executing controller twice

I understand AngularJS runs through some code twice, sometimes even more, like $watch events, constantly checking model states etc. 我了解AngularJS会在某些代码中运行两次，有时甚至更多，例如$watch事件，不断检查模型状态等。

However my code: 但是我的代码：

function MyController($scope, User, local) {var $scope.User = local.get(); // Get locally save user dataUser.get({ id: $scope.User._id.$oid }, function(user) {$scope.User = new User(user);local.save($scope.User);
});//...

Is executed twice, inserting 2 records into my DB. 执行两次，将2条记录插入到我的数据库中。 I'm clearly still learning as I've been banging my head against this for ages! 很显然，我一直在为此奋斗，我一直在学习！

---

#1楼

参考：https://stackoom.com/question/13BRw/对抗AngularJS执行控制器两次

---

#2楼

The app router specified navigation to MyController like so: 应用路由器将导航指定为MyController如下所示：

$routeProvider.when('/',{ templateUrl: 'pages/home.html',controller: MyController });

But I also had this in home.html : 但是我在home.html也有这个：

<div data-ng-controller="MyController">

This digested the controller twice. 这使控制器消化了两次。 Removing the data-ng-controller attribute from the HTML resolved the issue. 从HTML删除data-ng-controller属性可以解决此问题。 Alternatively, the controller: property could have been removed from the routing directive. 或者，可以从路由指令中删除controller:属性。

This problem also appears when using tabbed navigation. 使用选项卡式导航时也会出现此问题。 For example, app.js might contain: 例如， app.js可能包含：

  .state('tab.reports', {url: '/reports',views: {'tab-reports': {templateUrl: 'templates/tab-reports.html',controller: 'ReportsCtrl'}}})

The corresponding reports tab HTML might resemble: 相应的报告标签HTML可能类似于：

<ion-view view-title="Reports"><ion-content ng-controller="ReportsCtrl">

This will also result in running the controller twice. 这也将导致控制器运行两次。

---

#3楼

If you know your controller is unintentionally executing more than once, try a search through your files for the name of the offending controller, ex: search: MyController through all files. 如果您知道控制器无意中执行了多次，请尝试在文件中搜索有问题的控制器的名称，例如：search：MyController遍历所有文件。 Likely it got copy-pasted in some other html/js file and you forgot to change it when you got to developing or using those partials/controllers. 可能它已复制粘贴到其他html / js文件中，而当您开发或使用这些部件/控制器时却忘记了对其进行更改。 Source: I made this mistake 资料来源：我犯了这个错误

---

#4楼

AngularJS docs - ngController AngularJS文档-ngController
Note that you can also attach controllers to the DOM by declaring it in a route definition via the $route service. 请注意，您还可以通过$ route服务在路由定义中声明控制器，从而将控制器附加到DOM。 A common mistake is to declare the controller again using ng-controller in the template itself. 一个常见的错误是在模板本身中使用ng-controller再次声明控制器。 This will cause the controller to be attached and executed twice. 这将导致控制器被附加并执行两次。

When you use ngRoute with the ng-view directive, the controller gets attached to that dom element by default (or ui-view if you use ui-router). 当您将ngRoute与ng-view指令一起使用时，默认情况下，控制器将附加到该dom元素（如果使用ui-router，则为ui-view）。 So you will not need to attach it again in the template. 因此，您无需再次将其附加在模板中。

---

#5楼

Would like to add for reference: 补充说明：

Double controller code execution can also be caused by referencing the controller in a directive that also runs on the page. 也可以通过在页面上运行的指令中引用控制器来导致执行双控制器代码。

eg 例如

return {restrict: 'A',controller: 'myController',link: function ($scope) { ....

When you also have ng-controller="myController" in your HTML 当您在HTML中也有ng-controller =“ myController”时

---

#6楼

Just want to add one more case when controller can init twice (this is actual for angular.js 1.3.1): 只想在控制器可以两次初始化时再添加一种情况（这是angular.js 1.3.1的实际情况）：

<div ng-if="loading">Loading...</div>
<div ng-if="!loading"><div ng-view></div>
</div>

In this case $route.current will be already set when ng-view will init. 在这种情况下，当ng-view初始化时，$ route.current将已经被设置。 That cause double initialization. 这会导致双重初始化。

To fix it just change ng-if to ng-show/ng-hide and all will work well. 要解决此问题，只需将ng-if更改为ng-show / ng-hide，一切都会很好。