typescript: Singleton Pattern
npm init -y
npm install -g typescript
tsc --version
npm install -g ts-node
npm install eslint --save-dev
npm install typescript typescript-eslint-parser --save-dev
npm install eslint-plugin-typescript --save-dev
npm install --save-dev ts-loader
npm install --save-dev typescript ts-loader
npm install --save-dev webpack webpack-cli
npm install webpack
npm i -D webpack webpack-cli webpack-dev-server
npm install webpack webpack-cli typescript ts-loader --save-dev
npm i -D @babel/core @babel/preset-env babel-loader core-js
npm i -D less less-loader css-loader style-loader
npm i -D postcss postcss-loader postcss-preset-env
/**
* file: Singletonts.ts
* Singleton Pattern 单例是一种创建型设计模式， 让你能够保证一个类只有一个实例， 并提供一个访问该实例的全局节点。
* The Singleton class defines the `getInstance` method that lets clients access
* the unique singleton instance.
*/
class Singleton {
private static instance: Singleton;
/**
* The Singleton's constructor should always be private to prevent direct
* construction calls with the `new` operator.
*/
private constructor() { }
/**
* The static method that controls the access to the singleton instance.
*
* This implementation let you subclass the Singleton class while keeping
* just one instance of each subclass around.
*/
public static getInstance(): Singleton {
if (!Singleton.instance) {
Singleton.instance = new Singleton();
}
return Singleton.instance;
}
/**
* Finally, any singleton should define some business logic, which can be
* executed on its instance.
*/
public someBusinessLogic() {
// ...
}
}
/**
* The client code.
*/
function clientCodeDu() {
const s1 = Singleton.getInstance();
const s2 = Singleton.getInstance();
let stdu="";
if (s1 == s2) {
console.log('Singleton works, both variables contain the same instance.');
stdu="Singleton works";
} else {
console.log('Singleton failed, variables contain different instances.');
stdu="Singleton failed";
}
return stdu;
}
let ssig="gevindu";
let strsig=clientCodeDu();
let strsig1="geovindu";
let messagesig: string = 'Hello World,This is a typescript!,涂聚文 Geovin Du Web';
document.body.innerHTML = messagesig+","+strsig+","+strsig1+",TypeScript 单例模式"
調用：
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<head><title>TypeScript:单例模式</title>
<meta name="Description" content="geovindu,涂聚文,Geovin Du"/>
<meta name="Keywords" content="geovindu,涂聚文,Geovin Du"/>
<meta name="author" content="geovindu,涂聚文,Geovin Du"/>
</head>
<body>
<script src="dist/Singletonts.js"></script>
</body>
</html>
輸出：
npm install --save-dev ts-loader
npm install --save-dev webpack webpack-cli
npm install webpack
https://www.typescriptlang.org/docs/handbook/2/modules.html
https://www.typescriptlang.org/tsconfig#module
npm init -y
npm install --save-dev ts-loader
npm install --save-dev typescript ts-loader
npm install --save-dev webpack webpack-cli
npm install webpack
npm i -D webpack webpack-cli webpack-dev-server
npm install webpack webpack-cli typescript ts-loader --save-dev
npm i -D @babel/core @babel/preset-env babel-loader core-js
npm i -D less less-loader css-loader style-loader
npm i -D postcss postcss-loader postcss-preset-env
浙公网安备 33010602011771号