Angular6以往版本自定义environment配置在.angular-cli.json文件中，

1、在.angular-cli.json文件中 “environments中"添加

例如：

"environments": {
           "dev": "environments/environment.ts",
           "prod": "environments/environment.prod.ts",
           "simple": "environments/environment.simple.ts"
       }

2、编译命令

ng build --base-href /saturn/ --prod --env=simple
Angular6.x版本后，.angular-cli.json文件演变成angular.json文件
如果需要加自定义配置文件environment.simple.ts
1、在angular.json文件中如下配置：

     "configurations": {
          "production": {
                "fileReplacements": [
                    {
                        "replace": "src/environments/environment.ts",
                        "with": "src/environments/environment.prod.ts"
                      }
                ],
                "optimization": true,
                "outputHashing": "all",
                "sourceMap": false,
                "extractCss": true,
                "namedChunks": false,
                "aot": true,
                "extractLicenses": true,
                "vendorChunk": false,
                "buildOptimizer": true
                },
        "simple": {
            "fileReplacements": [
                 {
                    "replace": "src/environments/environment.ts",
                    "with": "src/environments/environment.simple.ts"
                  }
                ],
                "optimization": true,
                "outputHashing": "all",
                "sourceMap": false,
                "extractCss": true,
                "namedChunks": false,
                "aot": true,
                "extractLicenses": true,
                "vendorChunk": false,
                "buildOptimizer": true
            }
        }

2、无任何配置，默认编译prod命令
ng build --base-href /myweb/ --prod --configuration=production
如需使用simple环境，则执行命令
ng build --base-href /myweb/ --prod --configuration=simple