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...
el-dialog searched Baidu for this problem because z-index has a parent principle, and a solution is to add: modal-append-to-body= false or: append-to-body= true , to the el-dialog tag, but the el-dialog that previews the picture pop-up box is dyn...
is confused about why the function expression IIFE,function () {} (); reported an error immediately. ask whether the error is reported at the precompilation stage or during the execution of (). js interprets the function declaration in the "precompila...
br "^. {3} $ " ss= my Life sss=re.findall (spenem ss) sss [] ss= I sss=re.findall (spentry ss) sss [] s ^. {3} $ " ...
I read a lot of tutorials and said that process.nextTick was the first to be executed, but I was the last to run it myself. vue s nextTick is supposed to give priority to promise, but I also execute it after comparison when I run. what kind of task s...
<!-- modal header --> : class= "{ open : value} " how to understand. And how to use writing this style? ...