我是JS的新手。我正在学习JS OOP的概念。我正在尝试使用构造函数在JS中创建私有变量。但是当我尝试使用getters访问这些值时,我得到了一个错误'TypeError:'undefined‘is not a function’
function Card(n,s) {
var number = n;
var suit = s;
//getters
var getNumber = function(){
return this.number;
};
var getSuit = function(){
我有一个简单的库来选择一个元素并返回元素的对象。
(function() {
var $ = function(parameter) {
return new js(parameter);
};
var js = function(parameter) {
var selector;
selector = document.getElementById(parameter);
this = selector; // assign selector to this.
return this
从8更新到Angular 9导致循环依赖错误 我刚刚升级到Angular 9,并且已经修复了所有的编译错误。现在我得到了一个与循环依赖相关的错误,我无法跟踪它。 Error: Cannot instantiate cyclic dependency! ApplicationRef
at throwCyclicDependencyError (core.js:8072)
at R3Injector.hydrate (core.js:17049)
at R3Injector.get (core.js:16803)
at injectInjectorOnly (core.js:940)
at ɵɵ
我一直试图得到一个看似简单的例子,但一直未能使用MobX、React、TypeScript和actions。没有严格,一切正常,但我宁愿使用严格的模式。
我得到的错误是:
Uncaught Error: [mobx] Since strict-mode is enabled, changing observed observable values outside actions is not allowed. Please wrap the code in an `action` if this change is intended. Tried to modify: AppState@1.t
在一个平均堆栈应用程序中运行以下代码时,我一直会得到上面的错误:
$scope.completelesson = function(lessonindex, type) {
//a variable that will be appended to 'level' in order to access the level property of the user
var x = lessonindex + 1;
var level = 'level' + x;
var toupdate = {
我正在运行一个使用"@ckeditor/ckeditor5-angular": "1.2.3"和自定义的应用程序。我添加了SSR (服务器端渲染- Angular Universal)支持:
ng add @nguniversal/express-engine
当我运行npm run dev:ssr时,我得到了以下错误:
ReferenceError: window is not defined
at Object../node_modules/@ckeditor/ckeditor5-build-classic/build/ckeditor.