离子4添加构造函数参数时

Question

import { FormBuilder} from '@angular/forms';

这有效：

constructor(
) { }

但这不起作用：

constructor(
    private formBuilder: FormBuilder 
) { }

进行ionic serve

Answer 1

尝试在此处提到的添加反应性形式：

https://angular.io/guide/reeactive-forms#step-1- registering-the-reactive-forms-module

import { ReactiveFormsModule } from '@angular/forms';
@NgModule({
  imports: [
    // other imports ...
    ReactiveFormsModule
  ],
})
export class AppModule { }