topic description A method under the constructor (non-static method) does not want to execute the constructed method related codes Please paste the code text below (do not replace the code with pictures) class website extend site { ...
learn the constructor and encounter the following code when doing exercises the code is as follows function Fn(){ return this; } Fn.prototype.getNum = function(){ console.log(3); }; new new Fn().getNum (); Why is the output 3? what I under...
I have a base class, Base.php, that initializes the constructor. public function __construct() { parent::__construct(); $this->authWen(); } The constructor calls a permission verification method. However, in addition to true...
I encountered some confusion when learning the prototype chain as follows: in some blogs (such as Ruan Yifeng s blog), it is said: JavaScript natively provides Object objects, and all other objects inherit from Object objects, that is, those o...
JavaScript Advanced programming (3rd Edition) P144 the meaning expressed in (2). It s not what I understand. -reference elevation content start- English explanation To create a new instance of Person, use the new operator. Calling a constructor i...
I javascript A novice, recently encountered a problem that I have been unable to understand, as follows: var A = function() { return new B() } var B = function() { this.name = B } var a = A() console.log(Object.getPrototypeOf(a) == B.pro...
CPP11 allows list initialization for all objects, and because the constructor body is assigned, references and const variables must be initialized first, so you must use list initialization, so how is it initialized before CPP11? ...
when referencing popper.js, if packaging does not rule out popper.js, calling new PopperJS, an error will be reported let PopperJS = require( . popper ); let popper = new PopperJS(); PopperJS is not a constructor webpack.base.conf.js: ...
I js novice, recently encountered a little question when learning the content of the object, as follows: personal understanding: every time an instance object is generated using the new command, all the properties in the constructor will be define...
problem scenario: now you need to implement a drop-down refresh function, but in Wechat, the embedded browser of the nail, when you drop down. Will pull down the web page together, how to set the drop-down event, the problem will not occur when the page...
version information is "element-ui ": "^ 2.3.3 ", "vue ": "^ 2.5.2 " projects need to use element-ui paging component -- Pagination , and need to use multiple languages ( vue-i18n ) to support switching between Chinese and English. According...
problem description cannot be received at the front end of return JsonResponse after request.session assignment? related codes Please paste the code text below (do not replace the code with pictures) CheckLoginAccount = models.Account.objects...
var list = res.data.data; var arrPois = []; var lineColor = ""; GPSPoint var latlng = new google.maps.LatLng(39.92, 116.46); var myOptions = { zoom:20, center: latlng, mapTypeId...
some errors are Undefined index: password The category is like this . I have added @ not to report , but it will still be available on set_error_handler. can you skip the @? ...