在 angularjs 中的非作用域变量上添加监视 [英] add watch on a non scope variable in angularjs

问题描述

有没有办法将监视添加到非作用域变量.我想向局部变量添加一个手表.我有这样的东西

Is there a way to add watch to a non scope variable. I want to add a watch to local variable. I have something like this

 function EditAssetRegistryController(assetregistryService, manufacturerService, assettypeService, projectService, $localStorage, $routeParams) {
        var vm = this;
        vm.manufacturers = [];
        vm.projects = [];
        vm.asset_types = [];
        vm.ch_group_uniq = 'none';
}

这里有一种方法可以将监视添加到 vm.ch_group_uniq 吗?我知道如何使用作用域变量来完成，但我有一些场景，我必须检查许多复杂的变量.

here is there a way to add watch to vm.ch_group_uniq? I know how it will be done with scope variable but I have scenarios where I have to check many complex variables.

推荐答案

$watch 将无法像使用 controllerAs 的正常语法一样工作.你需要把它绑定到$scope，然后你就可以观察那个变量了:

$watch will not work as normal syntax with controllerAs. You need to bind it to $scope, and then you can watch that variable:

代码

$scope.$watch(angular.bind(this, function (ch_group_uniq) {
  return this.ch_group_uniq;
}), function (newVal, oldVal) {
  console.log('Name changed to ' + newVal);
});

这是参考托德格言文章

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