TypeScript 中的纯 Javascript 模块模式不会弄乱全局范围

Question

我作为纯 javascript 的前端开发人员已经有一段时间了。 正如您在下面的示例中看到的那样，我已经习惯了模块模式。现在我从 TypeScript 开始，我不可能得到相同的示例模式。目标是获得一种命名空间，以免破坏全球范围。 在 TypeScript 中实现相同目标的最佳方法是什么？谢谢

var myModulePattern = (function(){
    // Private properties - more or less
        var 
            moduleName = "myModulePattern",
            moduleAuthor = "Bob"
        ;
    // Private Methods - more or less
        function sayModuleHello (){
            return "Module " + moduleName + " made by " + moduleAuthor;
        }

    return {
    // Public properties
        createYear : 2018,
    // Public Methods
        greeting: function(){
            console.log("Hi: "+sayModuleHello());
            
        }
    }
})();

// Exits an alone object literal, so is no possible create another instance of the "class"
// Really, this is like a namespace to not mess up the global scope
myModulePattern.greeting();
console.log(myModulePattern.createYear);

Answer 1

这正是 namespaces 的用途。

namespace MyModule {
    // Private variables
    const moduleName = "myModulePattern";
    const moduleAuthor = "Bob";

    // Private functions
    function sayModuleHello() {
        return "Module " + moduleName + " made by " + moduleAuthor;
    }

    // Public properties
    export var createYear = 2018;
    // Public Methods
    export function greeting() {
        console.log("Hi: "+sayModuleHello());
    }
}

MyModule.greeting();
console.log(MyModule.createYear);

您可能还想将模块放在自己的文件中，这样您就不再需要 namespace 包装器了。

Answer 2

我建议您使用 typescript 类，如文档 https://www.typescriptlang.org/docs/handbook/classes.html 中所述

class myClassPattern {
    private className: string;
    private classAuthor: string;

    constructor(name: string, author: string) {
        this.className = name;
        this.classAuthor = author;

    }
    private sayClassHello():string{
      return "Class " + this.className + " made by " + this.classAuthor;
    }
    public greeting() {
        console.log("Hi: "+ this.sayClassHello());
    }
}

let greeter = new myClassPattern("myClassName", "myName");
greeter.greeting();