如何在angular 5 app中使用systemjs加载scss文件

Question

我创建了一个使用ASP MVC 5 angular 5。 我正在尝试使用systemJS将所有scss文件加载到名为main.css的文件中，这是我的system.js.config文件，

AnyCPU

及其加载程序文件

/**
 * System configuration for Angular samples
 * Adjust as necessary for your application needs.
 */
(function (global) {
  System.config({
    paths: {
      // paths serve as alias
      'npm:': 'node_modules/'
    },
    // map tells the System loader where to look for things
    map: {
      // our app is within the app folder
      'app': 'app',
      'components':'components',
      // angular bundles
      '@angular/core': 'npm:@angular/core/bundles/core.umd.js',
      '@angular/common': 'npm:@angular/common/bundles/common.umd.js',
      '@angular/compiler': 'npm:@angular/compiler/bundles/compiler.umd.js',
      '@angular/platform-browser': 'npm:@angular/platform-browser/bundles/platform-browser.umd.js',
      '@angular/platform-browser-dynamic': 'npm:@angular/platform-browser-dynamic/bundles/platform-browser-dynamic.umd.js',
      '@angular/http': 'npm:@angular/http/bundles/http.umd.js',
      '@angular/router': 'npm:@angular/router/bundles/router.umd.js',
      '@angular/forms': 'npm:@angular/forms/bundles/forms.umd.js',

      // other libraries
      'rxjs':                      'npm:rxjs',
      'angular-in-memory-web-api': 'npm:angular-in-memory-web-api/bundles/in-memory-web-api.umd.js'
    },
    // packages tells the System loader how to load when no filename and/or no extension
    packages: {
      app: {
        defaultExtension: 'js',
        meta: {
          './*.js': {
            loader: 'systemjs-angular-loader.js'
            },
            './*.html': {
                loader: 'systemjs-angular-loader.js'
            },
            './*.scss': {
                loader: 'systemjs-angular-loader.js',
                defaultExtension: 'css',
            }
        }
        },
        components: {
            defaultExtension: 'js',
            meta: {
                './*.js': {
                    loader: 'systemjs-angular-loader.js'
                },
                './*.html': {
                    loader: 'systemjs-angular-loader.js'
                },
                 './*.scss': {
                     loader: 'systemjs-angular-loader.js',
                     defaultExtension: 'css',
                }
            }
        },
      rxjs: {
        defaultExtension: 'js'
      }
    }
  });
})(this);

但我无法加载css文件，我在控制台中收到错误

http://localhost:60287/app/main/components/signup/signup.scss 404（未找到）