Nestjs没有从ConfigModule获得dotenv值

npm install dotenv

import { ConfigModule } from '@nestjs/config';
import { AppModule } from './app.module';
import * as dotenv from 'dotenv';

async function bootstrap() {
  // 加载dotenv文件
  dotenv.config();

  const app = await NestFactory.create(AppModule);

  // 配置ConfigModule
  app.configure(ConfigModule.forRoot({
    // 从dotenv中获取值
    envFilePath: '.env',
  }));

  await app.listen(3000);
}
bootstrap();

import { Module } from '@nestjs/common';
import { ConfigModule, ConfigService } from '@nestjs/config';
import { DatabaseService } from './database.service';

@Module({
  imports: [ConfigModule],
  providers: [DatabaseService],
})
export class DatabaseModule {
  constructor(private configService: ConfigService) {}

  // 使用ConfigService获取dotenv中的配置值
  getDatabaseConfig(): any {
    const host = this.configService.get('DB_HOST');
    const port = this.configService.get('DB_PORT');
    const username = this.configService.get('DB_USERNAME');
    const password = this.configService.get('DB_PASSWORD');

    return {
      host,
      port,
      username,
      password,
    };
  }
}