How to implement "Access-Control-Allow-Origin" header in asp.net

Configuring the CORS response headers on the server wasn't really an option. You should configure a proxy in client side.

Sample to Angular - So, I created a proxy.conf.json file to act as a proxy server. Below is my proxy.conf.json file:

{
  "/api": {
    "target": "http://localhost:49389",
    "secure": true,
    "pathRewrite": {
      "^/api": "/api"
    },
    "changeOrigin": true
  }
}

Put the file in the same directory the package.json then I modified the start command in the package.json file like below

"start": "ng serve --proxy-config proxy.conf.json"

now, the http call from the app component is as follows:

return this.http.get('/api/customers').map((res: Response) => res.json());

Lastly to run use npm start or ng serve --proxy-config proxy.conf.json