如何使用 SystemJS 模块启动 Typescript 应用程序? [英] How to start a Typescript app with SystemJS modules?

问题描述

我正在使用 typescript 编译器将我的模块捆绑到一个 main.js 文件中，使用 tsconfig.json 中的这些设置:

I am using the typescript compiler to bundle my modules into one main.js file, using these settings in tsconfig.json:

"module": "system",
"out": "docs/js/main.js"

这有效，因此根据 SystemJS 文档，我只需要包含 SystemJS 生产文件并在我的 HTML 中使用这些标签启动应用程序:

This works, so according to the SystemJS documentation, I only have to include the SystemJS production file and kickstart the app with these tags in my HTML:

<script src="js/system.js"></script>
<script>
  SystemJS.import('js/main.js');
</script> 

我的应用:

import { Message } from "./message";

export class App {
    constructor() {
        let demomessage = new Message("hello");
    }
}

export class Message {      
    constructor(str:string) {
        console.log(str);
    }
}

这会在 main.js 中生成此 javascript 代码:

This results in this javascript code in main.js:

System.register("message", ...) {
    // message code here
});
System.register("app", ...) {
    // app code here
});

我遗漏的部分(并且在 Microsoft 始终-缺少 Typescript-documentation) 是如何实际启动应用程序... SystemJS 如何知道哪个类是起点?即使我只是将 console.log 放在我的应用程序中它也不会执行....

The part that I'm missing (and that's also not explained in Microsoft's always-lacking-Typescript-documentation) is how to actually start the app... How does SystemJS know which class is the starting point? Even if I just put console.log in my app it doesn't execute....

编辑

我发现使用 system.js 而不是 system-production.js 至少可以启动这个过程.经过大量摆弄后，我让我的应用程序从以下代码开始，但它看起来很奇怪和丑陋.这是它应该如何工作???

I discovered that using system.js instead of system-production.js at least starts the process. After a lot of fiddling I got my app to start with the following code, but it looks weird and ugly. Is this how it's supposed to work???

<script src="js/system.js"></script>
<script>
  // get the anonymous scope
  System.import('js/main.js')
    .then(function() {
      // now we can get to the app and make a new instance
      System.import('app').then(function(m){
         let app = new m.App();
      })
    });
</script>

推荐答案

经过反复思考，我发现答案比预期的要简单:只需先将 bundle 作为常规 .js 文件加载，然后就可以导入直接应用:

After much head-scratching I found out the answer is more simple than expected: just load the bundle first as a regular .js file, and then you can import the app directly:

<script src="js/system.js"></script>
<script src="js/main.js"></script>
<script>
  System.import('app').then(function(module) {
    let a = new module.App();
  });
</script>

这篇关于如何使用 SystemJS 模块启动 Typescript 应用程序?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！