我将项目从Angular v5升级到Angular v6，但是出现以下错误：
错误：找不到本地工作区文件（'angular.json'）。
下面是我当前的 package.json
{
"name": "default",
"author": "",
"version": "0.0.0",
"license": "MIT",
"scripts": {
"ng": "ng",
"start": "ng serve",
"testbuild": "ng build --environment=test",
"preprodbuild": "ng build --environment=preprod",
"build": "ng build --prod",
"test": "ng test",
"lint": "ng lint",
"e2e": "ng e2e",
"postinstall": "npm run tsformat",
"tsformat": "tsfmt -r"
},
"private": true,
"dependencies": {
"@angular/animations": "^6.1.9",
"@angular/common": "^6.1.9",
"@angular/core": "^6.1.9",
"@angular/forms": "^6.1.9",
"@angular/http": "^6.1.9",
"@angular/platform-browser": "^6.1.9",
"@angular/platform-browser-dynamic": "^6.1.9",
"@angular/router": "^6.1.9",
"@ng-bootstrap/ng-bootstrap": "^3.2.2",
"@ngx-translate/core": "^10.0.2",
"@ngx-translate/http-loader": "^3.0.1",
"@types/jquery": "^3.3.10",
"angular2-csv": "^0.2.9",
"angular2-text-mask": "^9.0.0",
"classlist.js": "^1.1.20150312",
"core-js": "^2.5.7",
"enhanced-resolve": "^4.1.0",
"express": "^4.16.3",
"jquery": "^3.3.1",
"moment": "^2.22.2",
"ng-recaptcha": "^4.0.0",
"ngx-moment": "^3.1.0",
"ngx-restangular": "^3.0.0",
"ngx-spinner": "^6.1.2",
"ngx-store": "^2.0.0",
"npm": "^6.4.1",
"oauth": "^0.9.15",
"primeng": "^6.1.4",
"rxjs": "^6.3.3",
"rxjs-compat": "^6.3.3",
"to": "^0.2.9",
"typescript-formatter": "^7.2.2",
"update": "^0.7.4",
"xlsx": "^0.14.0",
"zone.js": "^0.8.26"
},
"devDependencies": {
"@angular-devkit/build-optimizer": "^0.8.4",
"@angular/compiler": "^6.1.9",
"@angular/compiler-cli": "^6.1.9",
"@angular/language-service": "^6.1.9",
"@ng-idle/core": "^6.0.0-beta.3",
"@ng-idle/keepalive": "^6.0.0-beta.3",
"express": "^4.16.3",
"typescript": "~2.9.2"
}
}