Difference: 1. The scope of class is larger than that of id. ID is unique and can only be called once in a page, while class can be called multiple times; 2. ID corresponds to the style selector of CSS. is "#", and the style selector corresponding to class in CSS is "."; 3. The priority of the id selector is higher than the class selector.
The operating environment of this tutorial: Windows 7 system, CSS3&&HTML5 version, Dell G3 computer.
Comparison of class and id in Html:
1. The scope of effect is different:
class has a larger range than id, which represents a unique identifier, just like our personal ID card. It is unique and can only be called once on a page. Generally, a web page does not have two or more IDs. The scope of class is wider. Class is a class label and can be called multiple times in an interface. Can be reused.
2. The syntax used is different:
How the id selector is used in css, such as using div as an example: (For example, there are div respectively id='i'...
and div class='c'...
Two div boxes, the methods quoted in css are as follows:)
.c{ 属性:属性值; } #i{ 属性:属性值; }
3. Priority The levels are different:
The priority of the id selector is higher than the priority of the class selector. For more important ones, you can use the id selector.
Recommended tutorial: "html video tutorial"
The above is the detailed content of What is the difference between id and class in html. For more information, please follow other related articles on the PHP Chinese website!

React'slimitationsinclude:1)asteeplearningcurveduetoitsvastecosystem,2)SEOchallengeswithclient-siderendering,3)potentialperformanceissuesinlargeapplications,4)complexstatemanagementasappsgrow,and5)theneedtokeepupwithitsrapidevolution.Thesefactorsshou

Reactischallengingforbeginnersduetoitssteeplearningcurveandparadigmshifttocomponent-basedarchitecture.1)Startwithofficialdocumentationforasolidfoundation.2)UnderstandJSXandhowtoembedJavaScriptwithinit.3)Learntousefunctionalcomponentswithhooksforstate

ThecorechallengeingeneratingstableanduniquekeysfordynamiclistsinReactisensuringconsistentidentifiersacrossre-rendersforefficientDOMupdates.1)Usenaturalkeyswhenpossible,astheyarereliableifuniqueandstable.2)Generatesynthetickeysbasedonmultipleattribute

JavaScriptfatigueinReactismanageablewithstrategieslikejust-in-timelearningandcuratedinformationsources.1)Learnwhatyouneedwhenyouneedit,focusingonprojectrelevance.2)FollowkeyblogsliketheofficialReactblogandengagewithcommunitieslikeReactifluxonDiscordt

TotestReactcomponentsusingtheuseStatehook,useJestandReactTestingLibrarytosimulateinteractionsandverifystatechangesintheUI.1)Renderthecomponentandcheckinitialstate.2)Simulateuserinteractionslikeclicksorformsubmissions.3)Verifytheupdatedstatereflectsin

KeysinReactarecrucialforoptimizingperformancebyaidinginefficientlistupdates.1)Usekeystoidentifyandtracklistelements.2)Avoidusingarrayindicesaskeystopreventperformanceissues.3)Choosestableidentifierslikeitem.idtomaintaincomponentstateandimproveperform

Reactkeysareuniqueidentifiersusedwhenrenderingliststoimprovereconciliationefficiency.1)TheyhelpReacttrackchangesinlistitems,2)usingstableanduniqueidentifierslikeitemIDsisrecommended,3)avoidusingarrayindicesaskeystopreventissueswithreordering,and4)ens

UniquekeysarecrucialinReactforoptimizingrenderingandmaintainingcomponentstateintegrity.1)Useanaturaluniqueidentifierfromyourdataifavailable.2)Ifnonaturalidentifierexists,generateauniquekeyusingalibrarylikeuuid.3)Avoidusingarrayindicesaskeys,especiall


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 Linux new version
SublimeText3 Linux latest version

SublimeText3 Chinese version
Chinese version, very easy to use

Dreamweaver CS6
Visual web development tools

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

WebStorm Mac version
Useful JavaScript development tools
