I am fairly new to node.js, and have a program that I have to set an environment variable in order to run (using the noble library, my bash command is: sudo NOBLE_HCI_DEVICE_ID=x node program.js, to tell my code which Bluetooth adapter - HCI device - to use).

我对node.js相当新，并且有一个程序我必须设置一个环境变量才能运行（使用高级库，我的bash命令是：sudo NOBLE_HCI_DEVICE_ID = x node program.js，告诉我的代码哪个蓝牙适配器 - HCI设备 - 使用）。

The reason behind this is that I have a number of modules, each needing their own Bluetooth adapter, and I wish to specify in my code which adapter each module should use.

这背后的原因是我有许多模块，每个模块都需要自己的蓝牙适配器，我希望在我的代码中指定每个模块应该使用哪个适配器。

I've found lots of articles telling me how to consume environment variables in my code and set them via the command line (process.env.VARIABLE_NAME), but nothing telling me how to set them from within node.js.

我发现很多文章告诉我如何在我的代码中使用环境变量并通过命令行（process.env.VARIABLE_NAME）设置它们，但没有告诉我如何在node.js中设置它们。

Is it possible to set the environment variables in my node.js code?

是否可以在我的node.js代码中设置环境变量？

Thanks

谢谢

3 个解决方案

// consume
var alreadySetEnvVarForDevice = process.env.NOBLE_HCI_DEVICE_ID

// set
process.env['NOBLE_HCI_DEVICE_ID'] = 1

var express = require('express');
var app = express();

// set the environment mode, default is process.env.NODE_ENV
app.set('env','development');

app.get('env');
// => 'development' 

export FOREVER_ROOT=/var/log/