错误错误:FormGroup期望FormGroup实例(Angular 5)

Question

我在Angular 5中有一个基本形式，但是释放以下错误。

这是错误：

editvisitantedialogcomponent.html：10错误错误：FormGroup期望 FormGroup实例。请传递一个。

示例：

> 
> <div [formGroup]="myGroup">   <input formControlName="firstName">
> </div>
> 
> In your class:

this.myGroup = new FormGroup({firstName：new FormControl((}(;在 function.ReactiveErrors.MissingFormException(forms.js：6347(at formGroupDirective._checkformpresent(forms.js：6852(at formGroupDirective.ngonchanges(forms.js：6623(at checkandupdatedireatextionline(core.js：12358(at checkandupdatenodeinline(core.js：13886(在checkandupdatenode处 (Core.JS：13829(在Debugcheckandupdatenode(Core.JS：14722( debugcheckdirectivesfn(core.js：14663(在object.eval [AS 更新导向](editvisitantedialogcomponent.html：10(at object.debugupdatedirectives [as Updatedirectives](core.js：14648( view_editvisitantedialogcomponent_0 @ editvisitantedialogcomponent.html：10

component.html

<div class="dialog-content-wrapper">
    <mat-toolbar matDialogTitle class="mat-accent m-0">
        <mat-toolbar-row fxLayout="row" fxLayoutAlign="space-between center">
            <span class="title dialog-title">Editar visitante</span>
            <button mat-button class="mat-icon-button" (click)="dialogRef.close()" aria-label="Close dialog">
                <mat-icon>close</mat-icon>
            </button>
        </mat-toolbar-row>
    </mat-toolbar>
   //esta linha que esta com o erro 
    <form name="form" [formGroup]="editForm" #f="ngForm">
        <div mat-dialog-content class="m-0 p-24" fusePerfectScrollbar>
            <div fxLayout="row" fxLayoutAlign="start start">
                <mat-icon class="mr-12 mt-12">label_outline</mat-icon>
                <mat-form-field class="mr-16">
                    <mat-select placeholder="Documento" formControlName="documento">
                        <mat-option value="option">Option</mat-option>
                    </mat-select>
                </mat-form-field>
                <mat-form-field>
                    <input matInput placeholder="Número" formControlName="numDocumento">
                </mat-form-field>
            </div>
            <div fxLayout="row" fxLayoutAlign="start start">
                <mat-icon class="mr-12 mt-12">account_circle</mat-icon>
                <mat-form-field fxFlex>
                    <input formControlName="nome" placeholder="Nome do Visitante" matInput required>
                </mat-form-field>
            </div>
            <div fxLayout="row" fxLayoutAlign="start start">
                <mat-icon class="mr-12 mt-12">group</mat-icon>
                <mat-form-field fxFlex>
                    <mat-select placeholder="Intenção" formControlName="motivoVisita">
                        <mat-option value="option">Familiar</mat-option>
                        <mat-option value="option">Particular</mat-option>
                        <mat-option value="option">Prestado de Serviço</mat-option>
                    </mat-select>
                </mat-form-field>
            </div>
            <div fxLayout="row" fxLayoutAlign="start start">
                <mat-icon class="mr-12 mt-12">lock_open</mat-icon>
                <mat-form-field fxFlex>
                    <mat-select placeholder="Autorização" formControlName="tipoAutorizacao">
                        <mat-option value="option">Lorem ipsum...</mat-option>
                    </mat-select>
                </mat-form-field>
            </div>
            <div fxLayout="row" fxLayoutAlign="start start">
                <div fxLayout="column">
                    <p>Quando?</p>
                    <mat-radio-group formControlName="periodoAutorizacao">
                        <mat-radio-button value="hoje">Hoje</mat-radio-button>
                        <mat-radio-button value="semanal" class="ml-8">Semanal</mat-radio-button>
                        <mat-radio-button value="periodo" class="ml-8">Período</mat-radio-button>
                    </mat-radio-group>
                    <div id="periodo" fxLayout="row" fxLayoutAlign="space-evenly start">
                        <mat-form-field fxFlex="45">
                            <input matInput [matDatepicker]="picker" placeholder="De" formControlName="periodoDe">
                            <mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
                            <mat-datepicker #picker></mat-datepicker>
                        </mat-form-field>
                        <mat-form-field fxFlex="45">
                            <input matInput [matDatepicker]="myDatepicker" placeholder="Até" formControlName="periodoAte">
                            <mat-datepicker-toggle matSuffix [for]="myDatepicker"></mat-datepicker-toggle>
                            <mat-datepicker #myDatepicker></mat-datepicker>
                        </mat-form-field>
                    </div>
                    <div id="semanal">
                        <mat-checkbox formControlName="diaSem1">Seg</mat-checkbox>
                        <mat-checkbox formControlName="diaSem2">Ter</mat-checkbox>
                        <mat-checkbox formControlName="diaSem3">Qua</mat-checkbox>
                        <mat-checkbox formControlName="diaSem4">Qui</mat-checkbox>
                        <mat-checkbox formControlName="diaSem5">Sex</mat-checkbox>
                        <mat-checkbox formControlName="diaSem6">Sáb</mat-checkbox>
                        <mat-checkbox formControlName="diaSem7">Dom</mat-checkbox>
                    </div>
                </div>
            </div>
            <div>
                <mat-form-field fxFlex>
                    <textarea matInput placeholder="Observação" formControlName="observacao"></textarea>
                </mat-form-field>
            </div>

        </div>
        <div mat-dialog-actions class="m-0 p-16" fxLayout="row" fxLayoutAlign="space-between center">
            <button mat-raised-button class="save-button mat-accent" aria-label="SAVE">
                SALVAR
            </button>
            <button mat-button class="mat-icon-button" aria-label="Delete" matTooltip="Excluir">
                <mat-icon>delete</mat-icon>
            </button>
        </div>
    </form>
</div>

component.ts

import { Component, OnInit, ViewEncapsulation } from '@angular/core';
import { FormControl, FormGroup, FormBuilder, Validators } from '@angular/forms';
@Component({
  selector: 'editvisitante',
  templateUrl: './editvisitante.component.html',
  styleUrls: ['./editvisitante.component.scss'],
  encapsulation: ViewEncapsulation.None
})
export class EditvisitanteComponent implements OnInit {
  editForm: FormGroup;
  constructor(private formBuilder: FormBuilder) {
  }
  ngOnInit() {
    this.editForm = this.formBuilder.group({
       documento: ["", Validators.required],
       numDocumento: ["", Validators.required],
       nome: ["", Validators.required],
       motivoVisita: ["", Validators.required],
       tipoAutorizacao: ["", Validators.required],
       periodoAutorizacao: ["", Validators.required],
       periodoDe: [""],
       periodoAte: [""],
       diaSem1: [""],
       diaSem2: [""],
       diaSem3: [""],
       diaSem4: [""],
       diaSem5: [""],
       diaSem6: [""],
       diaSem7: [""],
       observacao: ["", Validators.required],
    });
  }
}

Answer 1

如果任何新版本的Angular中的任何人都发生这种情况，这可能是原因 ->
如果您的ngoninit是异步方法，则必须先初始化您的表单组，然后再等待任何其他异步方法或某些异步代码

async ngOnInit() {
this.signinForm = new FormGroup({
  email: new FormControl("", [Validators.required, Validators.email]),
  password: new FormControl("", [
    Validators.required,
    Validators.pattern("^[a-zA-Z0-9]*"),
  ]),
});
///... other async code

}

Answer 2

我也遇到了这个问题。似乎由于某种原因，即使在构造函数或ngoninit中，HTML也在FormGroup面前处理。解决了我的错误是在超时将其包装的，尽管我不确定这是最好的或最清洁的解决方案。

setTimeout(() => {
  this.editForm = this.formBuilder.group({
     documento: ["", Validators.required],
     numDocumento: ["", Validators.required],
     nome: ["", Validators.required],
     motivoVisita: ["", Validators.required],
     tipoAutorizacao: ["", Validators.required],
     periodoAutorizacao: ["", Validators.required],
     periodoDe: [""],
     periodoAte: [""],
     diaSem1: [""],
     diaSem2: [""],
     diaSem3: [""],
     diaSem4: [""],
     diaSem5: [""],
     diaSem6: [""],
     diaSem7: [""],
     observacao: ["", Validators.required],
  });
), 1);