模块构建失败：TypeError：无法读取未定义的属性“sassLoader”答案

【问题标题】：Module build failed: TypeError: Cannot read property 'sassLoader' of undefined模块构建失败：TypeError：无法读取未定义的属性“sassLoader”
【发布时间】：2019-02-01 21:36:29
【问题描述】：

我已将 Angular5 更新到 Angular 6。到目前为止，我一直在使用 webpack-dev-server 来启动应用程序。我想让 ng serve 为应用程序提供服务。但是，当我运行 ng serve 时，我在下面收到此错误：- 模块构建失败：TypeError：无法读取未定义的属性“sassLoader” 在 getLoaderConfig (C:\Work\Dev\Accesslint-Checkins\Accesslint-UI\node_modules\sass-loader\index.js:389:39) 在 Object.module.exports (C:\Work\Dev\Accesslint-Checkins\Accesslint-UI\node_modules\sass-loader\index.js:42:23) ./src/assets/sass/app.scss 中的错误 (./node_modules/raw-loader!./node_modules/postcss-loader/lib??embedded!./node_modules/sass-loader??ref--15-3 !./src/assets/sass/app.scss)

以下是 angular.json，不知何故没有 angular-cli.json :-

{
  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",
  "version": 1,
  "newProjectRoot": "projects",
  "projects": {
    "Accesslint-ui": {
      "root": "",
      "sourceRoot": "src",
      "projectType": "application",
      "prefix": "app",
      "schematics": {},
      "architect": {
        "build": {
          "builder": "@angular-devkit/build-angular:browser",
          "options": {
            "outputPath": "dist/Accesslint-ui",
            "index": "src/index.html",
            "main": "src/main.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "src/tsconfig.app.json",
            "assets": [
              "src/favicon.ico",
              "src/assets"
            ],
            "styles": [
			"node_modules/bootstrap/scss/bootstrap.scss",
              "src/styles.scss",   
			  "src/assets/sass/app.scss"
            ],
            "scripts": []
          },
          "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
            }
          }
        },
        "serve": {
          "builder": "@angular-devkit/build-angular:dev-server",
          "options": {
            "browserTarget": "Accesslint-ui:build"
          },
          "configurations": {
            "production": {
              "browserTarget": "Accesslint-ui:build:production"
            }
          }
        },
        "extract-i18n": {
          "builder": "@angular-devkit/build-angular:extract-i18n",
          "options": {
            "browserTarget": "Accesslint-ui:build"
          }
        },
        "test": {
          "builder": "@angular-devkit/build-angular:karma",
          "options": {
            "main": "src/test.ts",
            "polyfills": "src/polyfills.ts",
            "tsConfig": "src/tsconfig.spec.json",
            "karmaConfig": "src/karma.conf.js",
            "styles": [
              "src/styles.css"
            ],
            "scripts": [],
            "assets": [
              "src/favicon.ico",
              "src/assets"
            ]
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": [
              "src/tsconfig.app.json",
              "src/tsconfig.spec.json"
            ],
            "exclude": [
              "**/node_modules/**"
            ]
          }
        }
      }
    },
    "Accesslint-ui-e2e": {
      "root": "e2e/",
      "projectType": "application",
      "architect": {
        "e2e": {
          "builder": "@angular-devkit/build-angular:protractor",
          "options": {
            "protractorConfig": "e2e/protractor.conf.js",
            "devServerTarget": "Accesslint-ui:serve"
          },
          "configurations": {
            "production": {
              "devServerTarget": "Accesslint-ui:serve:production"
            }
          }
        },
        "lint": {
          "builder": "@angular-devkit/build-angular:tslint",
          "options": {
            "tsConfig": "e2e/tsconfig.e2e.json",
            "exclude": [
              "**/node_modules/**"
            ]
          }
        }
      }
    }
  },
  "defaultProject": "Accesslint-ui"
}

【问题讨论】：

使用“npm cache clean --force”清除npm缓存并再次运行npm i

标签： css angular webpack sass

【解决方案1】：

另外请检查您在应用程序中使用的 node-sass 和 sass-loader 版本是什么。尝试使用可以解决此问题的最新版本。

这是我的应用程序中使用的版本

node-sass : 4.9.3
sass-loader: 7.1.0

【讨论】：

嗨，Suresh，抱歉耽搁了。安装了最新的 node-sass 和 sass-loader 仍然有同样的问题。还清除了缓存。