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升级Angular9 报错 Uncaught TypeError: Cannot set property ɵfac of function XXX which has only a getter，具体如下：
```js
ng-zorro-antd-mobile.js:10807 Uncaught TypeError: Cannot set property ɵfac of function ToastService(_appRef, _cfr, _zone) {
        this._appRef = _appRef;
        this._cfr = _cfr;
       ...<omitted>... } which has only a getter
    at ng-zorro-antd-mobile.js:10807
    at Module../node_modules/ng-zorro-antd-mobile/__ivy_ngcc__/fesm5/ng-zorro-antd-mobile.js (ng-zorro-antd-mobile.js:10818)
    at __webpack_require__ (bootstrap:84)
    at Module../src/app/login/login.component.ts (login.component.ts:1)
    at __webpack_require__ (bootstrap:84)
    at Module../src/app/app-routing.module.ts (app-routing.module.ts:1)
    at __webpack_require__ (bootstrap:84)
    at Module../src/app/app.module.ts (app.module.ts:1)
    at __webpack_require__ (bootstrap:84)
    at Module../src/main.ts (main.ts:1)
```
#### 原因
升级Angular 9 后默认开启Ivy enableIvy=true,
在这个情况下使用es5是会报错的。我们需要把es5换成es2015
在tsconfig.json将 `"target": "es5"`换为`"target": "es2015"`,然后重新编译，运行成功
```
{
  "compileOnSave": false,
  "compilerOptions": {
    "baseUrl": "./",
    "outDir": "./dist/out-tsc",
    "sourceMap": true,
    "declaration": false,
    "downlevelIteration": true,
    "experimentalDecorators": true,
    "module": "esnext",
    "moduleResolution": "node",
    "importHelpers": true,
    "target": "es2015",
    "typeRoots": [
      "node_modules/@types"
    ],
    "lib": [
      "es2018",
      "dom"
    ]
  },
  "angularCompilerOptions": {
    "fullTemplateTypeCheck": true,
    "strictInjectionParameters": true
  }
}

```