How to get process.env.ASPNETCORE_ENVIRONMENT in Typescript and Nodejs ? It is undefined?

I wrote this code in my .ts file

console.log(process.env.ASPNETCORE_ENVIRONMENT); // undefined

and defined ASPNETCORE_ENVIRONMENT as Development in Windows Environment.

but the log result is 'undefined' Why ?

How to use process.env in Typescript ? while I got it in my webpack config and it works perfectly but in Typescript not.

via user7489391