Tag:Block level

  • Functions of ES6 +: discrimination of VaR, let and const keywords


    Discrimination of VaR, let and const keywordsvar Variables with the same name can be defined repeatedly var name=’Bob’; var name=’Tom’; console.log(name) //Tom Variable promotion exists //JavaScript can promote variables a = 2 console.log(a); //2 var a //However, initialized variables cannot be promoted console.log(b); //undefined var b=3; No block level scope let arr=[]; for(var i=0;i<2;i++){ arr[i]=function(){ […]

  • Let and block level scope


    External variables within the block cannot be accessed if(true){ let foo = “mcgee0731” } console.log(foo); //foo is not defined … for(let i=0;i< 3;i++>){} console.log(i) //i is not defined Effect of VaR on cycle for(var i=0;i< 3;i++){ for(var i=0;i< 3;i++){ console.log(i); } } //When ‘I = 3’ reaches the outer loop after the inner loop, it […]

  • CSS attribute – overflow


    overflowDefinition: when the content of an element is too large to fitBlock Formatting Contexts How to display when. It isoverflow-xAndoverflow-yAttribute. value visible[default]The content will not be trimmed, and the overflow will appear outside the element box. hiddenOverflow content is clipped, invisible, and no scroll bar is provided. scrollThe overflow content is clipped, and the browser […]

  • CSS often test knowledge points


    This chapter introduces the knowledge of CSS. There are many things about CSS. The following are high-frequency test sites, which I hope will be helpful to you: 2.1 common selector Interviewer: please introduce the commonly used selectors and their priorities (basic questions) In CSS, a selector is a pattern for selecting elements that need to […]

  • New syntax in ES6 (I) — the difference between let, const and VaR


    ES6 introduction ES6, the abbreviation of ECMAScript 6.0, is the next generation standard of JavaScript language, which has been officially released and launched in June 2015. The purpose is to unify the Syntax Standard of JavaScript, which can be used to develop large-scale applications, which is called enterprise development language. Relationship between ES6 and javascript:ES6 […]

  • CSS float summary


    Introduction In the maintenance of some projects, we found many places to usefloatTo carry out layout, we know the effect of this attribute and how to solve related problems, but we can’t give a further reason, so let’s sort it out. Origin My GitHub appointment This is for understandingfloatInstead of comparing their advantages and disadvantages […]

  • The difference between VaR, const and let


    1. VAR has variable promotion, let and const do not What is variable promotion The declaration of functions and variables will be promoted to the top of functions, that is, functions and variables can be used first and then declared eg: console.log(a) ——undefind var a = 1 console.log(b,c) ——-error b is not defined let b=2; […]

  • Understanding and creation of BFC


    1、 Definition 1. BFC is short for block formatting context, which means block level formatting context. It is an independent block level rendering region, which has its own rendering rules and has nothing to do with the outside of the region;2. After rendering the interface, switch to debug mode, press Ctrl + Shift + C, […]

  • HTML and CSS design 01 — HTML framework and Tags


    HTML frames and Tags 1、 Framework 1. Set website Icon < link rel = “shortcut icon” a 2. Set the keywords and description of the website < meta name = “Keywords” content = “Keywords” > < meta name = “description” content = “description content” > 3. Writing scripts <script> ….. </script> 4. Writing style <style> […]

  • HTML and CSS design 04 — the core of CSS


    CSS core 1、 Box model Box model(https://segmentfault.com/a/11…) 2、 Display property: used to set the display mode of elements None: do not display elementsBlock: block display, setting line breaks before and after elements. Purpose: to convert row level labels to block level labels (row level labels do not set width and height, but can also set […]

  • ES6 Series 1: let and Const


    The rookie official account of “Code tailor” provides technical information and a series of basic articles for front-end developers. WeChat pays close attention to the public address of “little and mountain rookie”, and gets the latest articles in time. preface Before learning, we would like to tell you that this article is an introduction to […]

  • CSS of relearning front end (3) BFC and cascading context


    This article mainly introduces BFC and cascading context. Block formatting context (BFC) 1、 Definition of BFC  BFC (block formatting context): is an independent rendering area, the layout of elements inside the box will not affect the outside of the box. It belongs toOrdinary flow。 2、 Which methods create a block formatting context   1) root element (< […]