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Pass value from parent component to child component It is easy for the parent component to pass values to the child component. When directly referencing the child component in the parent component, the data is bound in the child component and received in the props attribute of the child component. The following is the ...

Why use promise? Solve callback hell fs.readFile(__dirname + '/data/a.txt', (err, data)=>{ if(!err){ console.log(data.toString()); fs.readFile(__dirname + '/data/b.txt', (err, data)=>{ if(!err){ console.log(data.toString()); } ...

Extensions to Arrays of ECMAScript 6 1. Extended Operators The extension operator (...) converts an array to a comma-separated sequence of parameters.Behind the extension operator is the invoked traverser interface, which can be used whenever an object with the traverser interface is deployed. let x ...

JavaScript 6. Object-Oriented Programming 6.1 Understanding Objects 6.1.1 Attribute Type 6.1.2 Define multiple attributes 6.1.3 Features for reading attributes 6.2 Create Objects 6.2.1 Factory Mode 6.2.2 Constructor Mode 6.2.2.1 Treat constructors as functions Problems with 6.2.2.2 Constructors ...

Article directory 1.JavaScript concept 2. Functions of JavaScript 3.JavaScript development history 4.JavaScript = ECMAScript + BOM+DOM 5.ECMAScript: the standard of client script language 5.1 basic grammar 5.1.1 combination with HTML 5.1.2 notes 5.1.3 data type 5.1.4 variable 5.1.5 operators 5.1.6 au ...

As Async/Await is officially incorporated into ES7 standard, more and more people are using this so-called asynchronous programming end level solution. However, the more await expressions are found in the process of use, the more redundant code is used to create Promise objects, and the sense of elegance plummets. For this reas ...

Article directory 1. Components of JavaScript 2. Operate BOM object 1).Window 2) . navigator 3).screen 4).location 5).document 6).history 3. Operate DOM object 1) . get dom node 2) . update node 3) . insert node 4) . delete node 4. Operation form 1. Components of JavaScript JavaScript consti ...

By studying Ruan Yifeng's Getting started with ECMAScript 6 , some knowledge points that Promise can easily forget new Promise((resolve, reject) => { reject() resolve() console.log('hello') }).then(() => { console.log('resolve'); }, () => { console.log('reject'); }) for (let ...

Preface The content of TypeScript fragrance series will be referenced Chinese Documents However, the examples in this paper will not duplicate those in the document, and will be studied in some places.In addition, the results of some of the examples in this article are compiled into JavaScript without ...

Catalog I. variables 2, Common data types 3, Control flow Four, function 5, Special objects I. variables 1. Variable format Starts with a letter, underscore (_), or dollar sign ($); subsequent characters can also be numbers (0-9) Case sensitive 2. Comment format //Single line notes /*Th ...