全局安装npm，仍然为每个Angular项目安装它给我错误，再次安装

Question

I have recently started learning Angular 4. So as mentioned in a tutorial I have installed nodejs, then angular 4 cli and create a project to start working. I did the same and looks perfect but when I use ng serve --open to run local server. It gives me following error:

I have solved this issue with installing npm again in my angular app directory.

Now I am going to create a new app which is giving the same error and I don't want to install npm again and again for each project (the issue is also solved by copying node_modules folder from first app root to the new app) because I am in a learning phase so I am required to create a new project for each new thing I learn.

Update: I am using Windows 8.1, latest version of Nodejs v8.1.4 (also tried the LTS), npm version 5.0.3 and Visual Studio Code. Everything installs perfectly without any error.

Answer 1

Any new project created with @angular/cli doesn't ship node_modules out of the box. You got to run npm install in every single proejct you create. (This is not the case with React CLI " create-react-app ".) The package json file is generated with every new project created. So just run npm install in the root folder.

Dont copy the node_modules folder of any existing project. It may have dev/production dependencies that you may not need in your new project so why keep junk.

The minimal package json created by CLI in your app folder has following scripts in place:

  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },

So if you do npm start or ng serve both will do the same.