我已将使用Angular 5应用程序的ASP.Net MVC从Angular 5.2更新到了8。

我已经遵循了Angular site的迁移步骤。

此particular thread on StackOverflow提到了针对Angular2的同一问题的解决方案，但在我看来，这些解决方案均无效。

到目前为止，我只知道SystemJS出现了问题，但是到目前为止，我仍然无法弄清。

This question也描述了类似的问题，但也没有帮助。

而且我们也从未使用过traceur软件包，但是以某种方式我遇到了错误。我已经检查了旧的package.json文件以及node_modules文件夹。

有人帮助我在这里丢失吗？我认为更新时会遗漏一些东西，但无法确切知道。

Package.config

{
  "name": "angular","version": "0.0.0","license": "MIT","scripts": {
    "ng": "ng","start": "ng serve","build": "ng build -prod -aot -vc -cc -dop --buildOptimizer","test": "ng test","lint": "ng lint","e2e": "ng e2e"
  },"private": true,"dependencies": {
    "@angular-devkit/build-optimizer": "^0.6.3","@angular/animations": "^8.2.13","@angular/common": "^8.2.13","@angular/compiler": "^8.2.13","@angular/core": "^8.2.13","@angular/forms": "^8.2.13","@angular/platform-browser": "^8.2.13","@angular/platform-browser-dynamic": "^8.2.13","@angular/router": "^8.2.13","@ng-bootstrap/ng-bootstrap": "^5.1.2","core-js": "^2.4.1","rxjs": "^6.5.3","systemjs": "0.19.40","tslib": "^1.10.0","zone.js": "~0.9.1"
  },"devDependencies": {
    "@angular-devkit/build-angular": "~0.803.16","@angular/cli": "^8.3.16","@angular/compiler-cli": "^8.2.13","@angular/language-service": "^8.2.13","@types/jasmine": "~2.8.3","@types/jasminewd2": "~2.0.2","@types/node": "~6.0.60","codelyzer": "^5.0.1","jasmine-core": "~2.8.0","jasmine-spec-reporter": "~4.2.1","karma": "~2.0.0","karma-chrome-launcher": "~2.2.0","karma-coverage-istanbul-reporter": "^1.2.1","karma-jasmine": "~1.1.0","karma-jasmine-html-reporter": "^0.2.2","protractor": "~5.1.2","ts-node": "~4.1.0","tslint": "~5.9.1","typescript": "~3.5.3","webpack-bundle-analyzer": "^2.12.0"
  }
}

Systemjs.config.js

(function (global) {
  System.config({
    paths: {
      'npm:': 'node_modules/'
    },map: {
      'app': 'app','@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/router': 'npm:@angular/router/bundles/router.umd.js','@angular/forms': 'npm:@angular/forms/bundles/forms.umd.js','@ng-bootstrap/ng-bootstrap': 'node_modules/@ng-bootstrap/ng-bootstrap/bundles/ng-bootstrap.js','@angular/common/http': 'npm:@angular/common/bundles/common-http.umd.js','tslib': 'npm:tslib/tslib.js','rxjs':                      'npm:rxjs'
    },packages: {
      app: {
        defaultExtension: 'ts',meta: {
          './*.js': {
            loader: 'systemjs-angular-loader.js'
          }
        }
      },rxjs: {
        defaultExtension: 'js'
      }
    }
  });
})(this);

tsconfig.json

{
  "compileonSave": true,"compilerOptions": {
    "downlevelIteration": true,"importHelpers": true,"sourceMap": true,"declaration": false,"moduleResolution": "node","emitDecoratorMetadata": true,"experimentalDecorators": true,"target": "es2015","typeRoots": [
      "node_modules/@types"
    ],"lib": [
      "es2017","dom"
    ],"module": "esnext","removeComments": true,"baseUrl": "./"
  }
}

src / tsconfig.app.json

{
  "extends": "./tsconfig.json","compilerOptions": {
    "types": []
  },"files": [
    "src/main.ts","src/polyfills.ts"
  ],"include": [
    "src/**/*.ts"
  ],"exclude": [
    "src/test.ts","src/**/*.spec.ts"
  ]
}

我在控制台中收到此错误。

(SystemJS) XHR error (404 Not Found) loading http://localhost:65309/traceur
    Error: XHR error (404 Not Found) loading http://localhost:65309/traceur
        at XMLHttpRequest.wrapFn (http://localhost:65309/node_modules/zone.js/dist/zone.js:1281:39)
        at ZoneDelegate.invoketask (http://localhost:65309/node_modules/zone.js/dist/zone.js:423:31)
        at Zone.runTask (http://localhost:65309/node_modules/zone.js/dist/zone.js:195:47)
        at Zonetask.invoketask [as invoke] (http://localhost:65309/node_modules/zone.js/dist/zone.js:498:34)
        at invoketask (http://localhost:65309/node_modules/zone.js/dist/zone.js:1693:14)
        at XMLHttpRequest.globalZoneAwareCallback (http://localhost:65309/node_modules/zone.js/dist/zone.js:1719:17)
    Error loading http://localhost:65309/traceur
    Unable to load transpiler to transpile http://localhost:65309/main.js
    Error loading http://localhost:65309/main.js