When I tried to run my Application, I got this exception

“The NPM script ‘start’ exited without indicating that the Angular CLI was listening for requests”

Background:

I was working on a project using Angular 5 SPA(Single Page Application) Template in Asp.Net Core 2.1. I created .net core application having Angular Cli support which is a really nice way to work with Angular.

Full Exception was something like this:

An unhandled exception occurred while processing the request.

AggregateException: One or more errors occurred. (One or more errors occurred. (The NPM script ‘start’ exited without indicating that the Angular CLI was listening for requests. The error output was: Unknown option: ‘–extractCss‘

InvalidOperationException: The NPM script ‘start’ exited without indicating that the Angular CLI was listening for requests. The error output was: Unknown option: ‘–extractCss‘

I thought that like most of the times angular application throw exceptions due to missing upgrades so I tried all the steps below but the problem was still there:

npm install -g @angular/cli
 npm install @angular/cli
 ng update @angular/cli
 ng update @angular/coresa

after wasting hours I finally managed to solve my problem.

Solution:

I edited my package.json file and remove the –extractCss parameter from the start and build property.

Click the Button Below to View Solution Code Example.

“scripts”: { “ng”: “ng”, “start”: “ng serve –extract-css”, “build”: “ng build –extract-css”,

to:

“scripts”: { “ng”: “ng”, “start”: “ng serve”, “build”: “ng build”,

Comment if you find this solution helpful or still facing the problem.