typescript 无法绑定到'formControl',因为它不是'input'的已知属性- Angular2材质自动完成问题

0qx6xfy6  于 2023-06-07  发布在  TypeScript
关注(0)|答案(9)|浏览(435)

我尝试在我的Angular 2项目中使用Angular Material Autocomplete组件。我在我的模板中添加了以下内容。

<md-input-container>
   <input mdInput placeholder="Category" [mdAutocomplete]="auto" [formControl]="stateCtrl">
</md-input-container>

<md-autocomplete #auto="mdAutocomplete">
   <md-option *ngFor="let state of filteredStates | async" [value]="state">
      {{ state }}
   </md-option>
</md-autocomplete>

以下是我的组件。

import {Component, OnInit} from "@angular/core";
import {ActivatedRoute, Router} from "@angular/router";
import {FormControl} from "@angular/forms";

@Component({
    templateUrl: './edit_item.component.html',
    styleUrls: ['./edit_item.component.scss']
})
export class EditItemComponent implements OnInit {
    stateCtrl: FormControl;
    states = [....some data....];

    constructor(private route: ActivatedRoute, private router: Router) {
        this.stateCtrl = new FormControl();
        this.filteredStates = this.stateCtrl.valueChanges.startWith(null).map(name => this.filterStates(name));
    }
    ngOnInit(): void {
    }
    filterStates(val: string) {
        return val ? this.states.filter((s) => new RegExp(val, 'gi').test(s)) : this.states;
    }
}

我得到以下错误。似乎找不到formControl指令。
无法绑定到“formControl”,因为它不是“input”的已知属性
这里的问题是什么?

f1tvaqid

f1tvaqid1#

在使用formControl时,您必须将ReactiveFormsModule导入到imports阵列。
示例:

import {FormsModule, ReactiveFormsModule} from '@angular/forms';

@NgModule({
  imports: [
    BrowserModule,
    FormsModule,
    ReactiveFormsModule,
    MaterialModule,
  ],
  ...
})
export class AppModule {}
h79rfbju

h79rfbju2#

忘记试图破译的例子。ts -正如其他人所说,它往往是不完整的。
相反,只需单击此处圈出的“弹出”图标,您将获得fully working StackBlitz example

您可以快速确认所需的模块:

注解掉ReactiveFormsModule的任何示例,你肯定会得到错误:

Template parse errors:
Can't bind to 'formControl' since it isn't a known property of 'input'.
v1l68za4

v1l68za43#

另一个可能发生这种情况的原因是:
在中使用formControl的组件未在导入ReactiveFormsModule的模块中声明。
因此,请检查声明抛出此错误的组件的模块。

xlpyo6sf

xlpyo6sf4#

从9.1.4版开始,您只需导入ReactiveFormsModule
https://angular.io/guide/reactive-forms

pod7payv

pod7payv5#

在angular 12中,matautocompleteModule的导入路径被更改,它解决了我的问题...现在它看起来像这个

fhg3lkii

fhg3lkii6#

首先向模板中添加一个常规的matInput。假设您使用ReactiveFormsModule中的formControl指令来跟踪输入的值。
React式表单提供了一种模型驱动的方法来处理值随时间变化的表单输入。本指南向您展示如何创建和更新简单的表单控件,如何在一个组中使用多个控件,如何验证表单值,以及如何实现更高级的表单。

import { FormsModule, ReactiveFormsModule } from "@angular/forms"; //this to use ngModule

...

imports: [
    BrowserModule,
    AppRoutingModule,
    HttpModule,
    FormsModule,
    RouterModule,
    ReactiveFormsModule,
    BrowserAnimationsModule,
    MaterialModule],
8iwquhpp

8iwquhpp7#

对我来说,最有效的方法是在@component({})中的模板``中构建表单,例如--

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

@Component({
  selector: 'app-contact-form',
  template:`
  <form class="validation-form" validate method="createUserWithEmailAndPassword">
  <div class="form-row">
    <div class="col-md-6 mb-3">
      <label for="firstName">First name</label>
      <input type="text" [formControl]="firstName" id="firstName" placeholder="Please enter your first name" required>
      <div class="valid-feedback">
        Looks good!
      </div>
    </div>
    <div class="col-md-6 mb-3">
      <label for="lastName">Last name</label>
      <input type="text" [formControl]="lastName" id="lastName" placeholder="Please enter your last name" required>
      <div class="valid-feedback">
        Looks good!
      </div>
    </div>
  </div>
    <div class="form-row">
      <div class="col-md-6 mb-3">
        <label for="email">Email address</label>
        <input type="email" [formControl]="email" id="email" aria-describedby="emailHelp" placeholder="Please enter your last name" required>
        <small id="emailHelp" class="form-text text-muted">We'll never share your email with anyone else.</small>
        <div class="valid-feedback">
          Looks good!
        </div>
      </div>
    </div>
    <div class="col-md-6 mb-3">
      <label for="password">Password</label>
      <input type="password" [formControl]="password" id="password" placeholder="Please enter your password" required>
      <div class="valid-feedback">
        Looks good!
      </div>
    </div>
    <div class="col-md-3 mb-3">
      <label for="zip">Zip</label>
      <input type="text" [formControl]="zip" id="zip" required>
      <div class="invalid-feedback">
        Please provide a valid zip.
      </div>
    </div>
  </div>
  <div class="form-group">
    <div class="form-check">
      <input class="form-check-input" type="checkbox" value="" id="invalidCheck" required>
      <label class="form-check-label" for="invalidCheck">
        Agree to terms and conditions
      </label>
      <div class="invalid-feedback">
        You must agree before submitting.
      </div>
    </div>
  </div>
  <button class="btn btn-primary" type="submit">Submit form</button>
</form>`,

  templateUrl: './contact-form.component.html',
  styleUrls: ['./contact-form.component.scss']
})
export class ContactFormComponent implements OnInit {

  firstName =  new FormControl('');
  lastName =  new FormControl('');
  email =  new FormControl('');
  password =  new FormControl('');

  constructor() { }

  ngOnInit(): void {
  }

}

这停止显示错误。如果错误仍然存在,那么这可以为您解决

0s7z1bwu

0s7z1bwu8#

对我有效的是将我的进口转移到我的申报和出口之前,不知道为什么这有效,但它确实有效。

@NgModule({
  imports: [
    CommonModule,
    FormsModule,
    ReactiveFormsModule,
    MatSlideToggleModule,
  ],
  declarations: [SettingsComponent],
  exports: [
    SettingsComponent
  ]
})
export class SettingsModule { }
2eafrhcq

2eafrhcq9#

如果你使用的是独立组件,ReactiveFormsModule的导入必须在自己的组件中,而不是app.module.ts。

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

@Component({
  selector: 'app-form',
  templateUrl: './form.component.html',
  styleUrls: ['./form.component.css'],
  standalone: true,
  imports: [ ReactiveFormsModule ]
})
export class FormRecipesComponent {

constructor() {}

name = new FormControl('');

}

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