Programmer Think

Create array The Array constructor creates an Array Create an empty array var arr = new Array();//[] arr.length //0 Create an array with a length of 10 var arr = new Array(10) arr.length //10 Creates an array containing the specified element //The data type of each element of the array in ECMAScript can be different var arr = new Array ...

The implicit object of application is javax servlet. An instance of ServletContext. It is mainly used to obtain initialization parameters and share attributes and their values throughout the JSP Application, which means that any attribute set by the implicit object of the application can be used for all JSP pages. method: Object get property ...

1, Constructors and prototypes 1. Why can the new operator create an instance object? (1) Create a new empty object in memory. (2) Inherit the prototype of the constructor. (3) this points to the new object and calls the constructor. (4) Returns a new object.   2. Prototype and prototype chain (1) Prototype Each function has a prototyp ...

1, What is cross domain? In the front-end field, cross domain refers to that the browser allows to send cross domain requests to the server, so as to overcome the limitation that Ajax can only be used in the same source. When cross domain, you will receive the following error 2, What is homology strategy? Homology policy is an agreement. ...

❉ 520 on Valentine's day, I sent a gift to my girlfriend with code ~ html+css+javascript to realize the cherry blossom love album "you can take it to the person you like" The annual / 520 Valentine's Day / Tanabata Valentine's Day / birthday gift / advertising younger martial sister / Christmas / New Year's Day / New Year's Day / pro ...

1, Basic concepts of class class writing is just a syntax sugar. It just makes the writing of object prototype clearer and more like the syntax of object-oriented programmingThe internal default of classes and modules is strict modeClass does not have variable promotion 2, constructor method 1. Constructor method is the default method of ...

preface: Before that, let's first introduce that Js is a single threaded language. The code is executed from top to bottom. When encountering synchronous code, it will not stop when some code is asynchronous. If it stops, it will be very time-consuming, so there is the concept of task queue at this time. When encountering asynchronous code, In ...

js has three steps: 1. Syntax analysis; 2. Precompiling; 3. Interpretation and execution There are two types of precompiling: first, global precompiling; 2, Partial precompiling. It is precisely because of precompiling that there are variable promotion (excluding assignment) and overall function declaration promotion in js. Global pre ...

I wrote an article about vue2 X's responsive principle, but because vue3 also came and followed the pace of vue3, I began to learn the responsive principle of vue3 on Monday. You should have heard that vue3 uses proxy to solve the responsive principle, and it solves the object in vue2 Definepropery has some problems, but it also brings s ...

1. Ecological use around the framework Frame limited to vue2 xAt present, the company's R & D and delivery of medium-sized and large-scale projects, so vuex and Vue router must be usedThe UI is based on elementui, and the MD UI developed by the experience design department is used to eliminate elementui in subsequent developmentThe tool li ...