升级到最新版本，现在ng serve给了我错误

Question

我在当前的Angular 2 CLI项目中升级到了1.0.0-beta.11-webpack.8，同时也更新了我的Angular - CLI。以匹配升级后的CLI的期望属性。当我运行ng serve时，我得到这个错误:

`Cannot read property 'length' of undefined
TypeError: Cannot read property 'length' of undefined
    at Object.getWebpackCommonConfig (/Applications/MAMP/htdocs/learnloop/node_modules/angular-cli/addon/ng2/models/webpack-build-common.ts:23:25)
    at new NgCliWebpackConfig (/Applications/MAMP/htdocs/learnloop/node_modules/angular-cli/addon/ng2/models/webpack-config.ts:13:30)
    at Class.exports.default.Task.extend.run (/Applications/MAMP/htdocs/learnloop/node_modules/angular-cli/addon/ng2/tasks/serve-webpack.ts:19:22)
    at /Applications/MAMP/htdocs/learnloop/node_modules/angular-cli/addon/ng2/commands/serve.ts:84:26
    at process._tickCallback (internal/process/next_tick.js:103:7)`

我为此纠结了一段时间，但在运行了所有这些命令并使Angular CLI不再处于破碎状态后，我遇到了这个问题。下面是我运行的命令:

`npm uninstall -g angular-cli
npm cache clean
npm install -g angular-cli@webpack
rm -rf node_modules dist tmp typings
npm install --save-dev angular-cli@webpack`

最后，这里是我正在运行的node、npm和Angular CLI的版本:

Node v6.4.0 NPM 3.10.3 angular-cli: 1.0.0-beta.11-webpack.8

这里是我的angular-cli.json:

`{
  "project": {
    "version": "1.0.0-beta.11-webpack.8",
    "name": "learnloop"
  },
  "apps": [
    {
      "main": "src/main.ts",
      "tsconfig": "src/tsconfig.json",
      "mobile": false,
      "prefix": "app",
      "root": "src",
      "styles": [
        "styles.scss"
      ]
    }
  ],
  "addons": [],
  "packages": [],
  "e2e": {
    "protractor": {
      "config": "config/protractor.conf.js"
    }
  },
  "test": {
    "karma": {
      "config": "config/karma.conf.js"
    }
  },
  "defaults": {
    "styleExt": "scss",
    "prefixInterfaces": false,
    "lazyRoutePrefix": "+"
  }
}`

我为这一大堆文字道歉，但我想确保你们所有人都有可能帮助解决这个问题所需的一切。我哪里做错了?

Answer 1

我设法让这个工作。试着把它粘贴到angular-cli中。Json(相应地编辑):

{
  "project": {
    "version": "1.0.0-beta.11-webpack.8",
    "name": "<name-of-app>"
  },
  "apps": [
    {
      "root": "src",
      "outDir": "dist",
      "assets": "assets",
      "index": "index.html",
      "main": "main.ts",
      "test": "test.ts",
      "tsconfig": "tsconfig.json",
      "prefix": "app",
      "mobile": false,
      "styles": [
        "styles.scss"
      ],
      "scripts": [],
      "environments": {
        "source": "environments/environment.ts",
        "prod": "environments/environment.prod.ts",
        "dev": "environments/environment.dev.ts"
      }
    }
  ],
  "addons": [],
  "packages": [],
  "e2e": {
    "protractor": {
      "config": "./protractor.conf.js"
    }
  },
  "test": {
    "karma": {
      "config": "./karma.conf.js"
    }
  },
  "defaults": {
    "styleExt": "scss",
    "prefixInterfaces": false,
    "lazyRoutePrefix": "+"
  }
}

然后在根工程目录下输入ng init。它会要求你替换一堆不同的文件，或者保留它们。文件之间有一些细微的差异，特别是在app.module.ts内部，所以请确保先提交，因为文件结构和文件内部的代码会有一些变化。

Answer 2

尝试将nodejs版本更新到最新版本(当前为v.7.2)。在ng server失败的情况下，