Is it possible to execute vanilla javascript before angular boot?

Question

I want to execute a javascript snippet that check whatever the browser supports angular or not. In the second case the script will do a redirect towards a static html webpage.

My intent is not rely on polyfills to support outdated browsers, but give a nice UX anyway by inviting the visitor to access my website with a modern browser.

Is it possible?

Angular might already be booting then though. Your main.ts file might be a better spot.. — MikeOne, Jul 31 '21 at 18:09
@aviadP. wouldn't in that way be executed in each page of my angular app? — Phate, Jul 31 '21 at 21:36
Angular is a SPA, so `index.html` is processed once, then all the view changes are performed in javascript — Aviad P., Jul 31 '21 at 21:41

score 1 · Answer 1 · answered Aug 01 '21 at 17:29

1

In your main.ts

//replace this
//    platformBrowserDynamic().bootstrapModule(AppModule)
//      .catch(err => console.error(err));

//by some like:

if (executeAjavaScriptFunction())
{
  platformBrowserDynamic().bootstrapModule(AppModule)
     .catch(error=>console.log(error))
}
else
{
  alert("improve your navigator");
}

Or you can also write in your .html some like

  <app-root>
   If you can't see the application visit www.myoldpage.com
  </app-root>

answered Aug 01 '21 at 17:29

Eliseo

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But...if I wrote it inside of main.ts wouldn't I be forced to compile as es5 for it to be processed in IE? Moreover, wouldn't the compiler give me error if I used something like window.agent? – Phate Aug 01 '21 at 18:04

Is it possible to execute vanilla javascript before angular boot?

1 Answers1