从 Angular 表达式访问窗口 [英] Accessing the window from Angular expression

问题描述

根据 开发人员指南，我应该能够从 Angular 表达式内部访问浏览器窗口使用 $window.

According to the developer guide I should be able to access the browser window from inside Angular expressions with $window.

与 JavaScript 的名称默认为全局窗口属性不同，Angular 表达式必须使用 $window 来引用全局窗口对象.例如，如果要调用定义在 window 上的 alert()，则必须在表达式中使用 $window.alert().

Unlike JavaScript, where names default to global window properties, Angular expressions have to use $window to refer to the global window object. For example, if you want to call alert(), which is defined on window, in an expression you must use $window.alert().

但是我似乎无法从用 $scope.$eval 计算的表达式访问 $window.以下是我退出控制台时得到的一些输出:

However I can't seem to access $window from expressions evaluated with $scope.$eval. Here are some outputs I get when logging out to the console:

console.log($window);                   // the Window object as expected
console.log($scope.$eval('$window'));   // undefined
console.log($scope.$eval('1+1'));       // 2
console.log($scope.$eval('scopeVar'));  // 'abc'

控制器具有 $window 作为依赖项.我可以从表达式访问范围变量和其他服务，但不能访问 $window，所以 $scope.$eval($window.alert()) 也不起作用.

The controller has $window as a dependency. I can access scope variables and other services from expressions but not $window, so $scope.$eval($window.alert()) doesn't work either.

我在这里遗漏了什么?

推荐答案

$scope.$eval 根据 $scope 进行评估，因此您的评估只有在您将 $window 服务分配给作用域成员:

$scope.$eval evaluates against the $scope, so your evaluation will work only if you assign $window service to scope member:

$scope.$window = $window;  
console.log($scope.$eval('$window'));

这篇关于从 Angular 表达式访问窗口的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！