Utilizing Typescript for Front-End Development

Lately, I've been facing a challenge with my Typescript project. I'm working on connecting Typescript to a database and displaying the results in the browser. However, I keep encountering console errors like:

Uncaught ReferenceError: exports is not defined ("export class Database")

Uncaught ReferenceError: require is not defined ("import {Database} from "./Database";") 

It seems that the files are being transpiled to a CommonJS module which the browser can't interpret.

My question is: Am I correct in diagnosing the issue this way? And what would be the best solution to resolve it?

Some suggestions recommend using WebPack or Browserify, while others mention AMD/SystemJS or RequireJS. I'm also interested in exploring Gulp and Webpack for this purpose but unsure of where to begin or how it fits into the workflow.

Here's a snippet of the Database Class:

export class Database{
    //...
}

And the Mongo Class:

<reference path="../../../typings/browser/ambient/node/index.d.ts" />
<reference path="../../../typings/browser/ambient/mongodb/index.d.ts" />

    import {IDatabase} from "../interfaces/IDatabase";
    import {Database} from "./Database";
    import {MongoClient} from "mongodb";

    class MongoDB extends Database implements IDatabase{
        //...
    }

As well as the Database Interface:

export interface IDatabase{
    //...
}

Lastly, here are some TSConfig Options:

"target": "es6",
"module": "commonjs",
"moduleResolution": "classic",
"sourceMap": true,

Answer №1

Below, you will find some helpful resources to kickstart your journey:

  1. Getting started with Webpack: link
  2. Utilizing Gulp along with Webpack: link
  3. Introduction to Browserify: link
  4. Understanding Systemjs: link, link
  5. Exploring requirejs: link
  6. A sample gulp task for reference: link
  7. Implementing a basic systemjs configuration in index.html: link

There isn't a one-size-fits-all solution - the best approach depends on your specific application requirements. If you need to bundle everything into a single js file, consider using webpack or browserify. Otherwise, systemjs or requirejs may be more suitable. Personally, I prefer using gulp with systemjs. However, as demonstrated by links 1-5, it's possible to achieve this with any loader.

Current browsers are not capable of loading javascript modules directly, which is why loaders like webpack, requirejs, systemjs, and browserify are necessary. Choosing one of these loaders, configuring it properly, can help eliminate the errors you've encountered.

We hope these resources will assist you in taking the first steps towards your goal.

Answer №2

Through some troubleshooting, I was able to resolve the problem at hand. It turns out that I was unnecessarily linking these files directly in the "index.html" page. Rather than doing that, all I needed to do was adjust the file references so that the Node controller could locate them instead of relying on the index page. Once this change was made and the code was compiled, the export and require functions functioned perfectly.

Answer №3

Using the tsc command line tool is essential for working with TypeScript in the browser.

To begin, set the module to 'AMD' in the tsconfig.json file:

{
  "compilerOptions": {
    "module": "amd",
    "outDir": "./", //Default setting
    "rootDir": "./" //Default setting
  }
}

Next, create a simple index.html that utilizes the entry file index.js to initialize the application using require.js:

<html>
  <body>
    <div id="me">Nothing</div>

    <script data-main="./index.js" src="https://cdn.bootcss.com/require.js/2.3.6/require.min.js"></script>
  </body>
</html>

Then, start writing your code in the index.ts file:

//import something from somewhere

const el : HTMLElement | null = document.getElementById('me');
if(el){
  el.innerHTML = 'Hey I am typescript!';
}

You can also import other files as you normally would in TypeScript.

Finally, compile all the files using the tsc command and open the index.html file to see the results.

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