临时

import {Component, OnInit} from '@angular/core';
import {FormArray, FormBuilder, FormControl, FormGroup} from '@angular/forms';

@Component({
  selector: 'app-reactived-form',
  templateUrl: './reactived-form.component.html',
  styleUrls: ['./reactived-form.component.css']
})
export class ReactivedFormComponent implements OnInit {

  public formModel: FormGroup;
  public fb: FormBuilder = new FormBuilder();
  constructor() {

/*    this.formModel = this.fb.group({
      nickName: [''],
      emails: this.fb.array([['']]),
      passwordInfo: this.fb.group({
        password: [''],
        passwordConfirm: ['']
      })
    });*/

    this.formModel = new FormGroup({
      nickName: new FormControl(),
      emails: new FormArray([new FormControl(), new FormControl()]),
      passwordInfo: new FormGroup({
          password: new FormControl(),
          passwordConfirm: new FormControl()
        }
      )
    });
  }
  createUser() {
    let n = this.formModel.get('nickName') as FormControl;
    console.log(n.value);
  }
  addEmail() {
    let emails = this.formModel.get('emails') as FormArray;
    emails.push(new FormControl());
    console.log(this.formModel.value);
  }
  ngOnInit() {
  }

}

<form [formGroup]="formModel" (submit)="createUser()">
  <div>昵称：<input formControlName="nickName" pattern="[a-zA-Z0-9]"></div>
  <div>邮箱：
    <ul formArrayName="emails">
      <li *ngFor="let email of formModel.get('emails').controls; let i= index">
        <input [formControlName]="i">
      </li>
    </ul>
    <button (click)="addEmail()">添加email</button></div>
  <div [formGroup]="formModel.get('passwordInfo')">
    <div>密码：<input formControlName="password" type="password"></div>
    <div>确认密码：<input formControlName="passwordConfirm" type="password"></div>
  </div>
  <div>
    <button type="submit">注册</button>
  </div>
</form>

import {Component, OnInit} from '@angular/core';

@Component({
  selector: 'app-template-form',
  templateUrl: './template-form.component.html',
  styleUrls: ['./template-form.component.css']
})
export class TemplateFormComponent implements OnInit {

  constructor() {
  }

  ngOnInit() {
  }

  createUser(values) {
    console.log('createUser');
  }
}

<form #myForm="ngForm" (ngSubmit)="createUser(myForm.value)">
  <div>昵称：<input ngModel name="nickname" pattern="[a-zA-Z0-9]"></div>
  <div>邮箱：<input ngModel name="email" type="email"></div>
  <div ngModelGroup="passwordInfo">
    <div>密码：<input ngModel name="password" type="password"></div>
    <div>确认密码：<input ngModel name="password" type="password"></div>
  </div>
  <div><button type="submit">注册</button></div>
</form>