entityMap|blocks|key|5fuge|text|我通过添加|type|unstyled|depth|inlineStyleRanges|entityRanges|data|ag4os|属性添加到包含|898co|属性。^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|G|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|H|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|I|9|@]|A|@]|B|$]]]]

I fixed this error by adding the <code>name="fieldName" ngDefaultControl</code> attributes to the element that carries the <code>[(ngModel)]</code> attribute.

entityMap|blocks|key|df4h0|text|我也遇到了同样的问题，问题是我的子组件有一个|type|unstyled|depth|inlineStyleRanges|entityRanges|data|93a22|命名|c761o|..。|8dge|所以我只需要改变一下：|asuba|至：|fpm6p|ts：|c16ah|@Input()
control:FormControl;|code-block|syntax|javascript^0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|R|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|S|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|T|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|U|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|V|9|@]|A|@]|B|$]]|$2|K|4|L|6|7|8|W|9|@]|A|@]|B|$]]|$2|M|4|N|6|O|8|X|9|@]|A|@]|B|$P|Q]]]]

I had the same problem and the issue was that my child component had an <code>@input</code> named <code>formControl</code>. 

So I just needed to change from:

<pre><code>&lt;my-component [formControl]="formControl"&gt;&lt;my-component/&gt;
</code></pre>

to:

<pre><code>&lt;my-component [control]="control"&gt;&lt;my-component/&gt;
</code></pre>

ts:

<pre><code>@Input()
control:FormControl;
</code></pre>

entityMap|blocks|key|ceqk2|text|这有点傻，但是我意外地使用了|type|unstyled|depth|inlineStyleRanges|entityRanges|data|7r8a9|而不是|4h4rs|..。请看这里：|e8f5c|错误的|7lt4s|@Component({
++selector:+'app-application-purpose',
++template:+`
+++++
++++++
++++
++`
})
export+class+MyComponent+implements+OnInit+{
++formGroup:+FormGroup

++constructor(
++++private+formBuilder:+FormBuilder
++)+{+}

++ngOnInit()+{
++++this.formGroup+=+this.formBuilder.group({
++++++formGroupProperty:+''
++++})
++}
}|code-block|syntax|javascript|3sqbs|正确|clujh|@Component({
++selector:+'app-application-purpose',
++template:+`
+++++
++++++
++++
++`
})
export+class+MyComponent+implements+OnInit+{
++formGroup:+FormGroup

++constructor(
++++private+formBuilder:+FormBuilder
++)+{+}

++ngOnInit()+{
++++this.formGroup+=+this.formBuilder.group({
++++++formGroupProperty:+''
++++})
++}
}^0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|R|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|S|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|T|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|U|9|@]|A|@]|B|$]]|$2|I|4|J|6|K|8|V|9|@]|A|@]|B|$L|M]]|$2|N|4|O|6|7|8|W|9|@]|A|@]|B|$]]|$2|P|4|Q|6|K|8|X|9|@]|A|@]|B|$L|M]]]]

This is kind of stupid, but I got this error message by accidentally using <code>[formControl]</code> instead of <code>[formGroup]</code>. See here:

WRONG

<pre class="lang-js prettyprint-override"><code>@Component({
 selector: 'app-application-purpose',
 template: `
 &lt;div [formControl]="formGroup"&gt; &lt;!-- '[formControl]' IS THE WRONG ATTRIBUTE --&gt;
 &lt;input formControlName="formGroupProperty" /&gt;
 &lt;/div&gt;
 `
})
export class MyComponent implements OnInit {
 formGroup: FormGroup

 constructor(
 private formBuilder: FormBuilder
 ) { }

 ngOnInit() {
 this.formGroup = this.formBuilder.group({
 formGroupProperty: ''
 })
 }
}
</code></pre>

RIGHT

<pre class="lang-js prettyprint-override"><code>@Component({
 selector: 'app-application-purpose',
 template: `
 &lt;div [formGroup]="formGroup"&gt; &lt;!-- '[formGroup]' IS THE RIGHT ATTRIBUTE --&gt;
 &lt;input formControlName="formGroupProperty" /&gt;
 &lt;/div&gt;
 `
})
export class MyComponent implements OnInit {
 formGroup: FormGroup

 constructor(
 private formBuilder: FormBuilder
 ) { }

 ngOnInit() {
 this.formGroup = this.formBuilder.group({
 formGroupProperty: ''
 })
 }
}
</code></pre>

entityMap|blocks|key|e7q8d|text|当我在Angular+7中编写自定义表单控件组件时，我也收到了这个错误。然而，没有一个答案适用于Angular+7。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5dttn|在我的示例中，需要将以下内容添加到|2pv5h|装饰者：|5du4j|providers:+[
++++{
++++++provide:+NG_VALUE_ACCESSOR,
++++++useExisting:+forwardRef(()+=>+MyCustomComponent),++//+replace+name+as+appropriate
++++++multi:+true
++++}
++]|code-block|syntax|javascript|ek662|这是一个“我不知道它为什么有效，但它确实有效”的案例。将其归因于Angular部分糟糕的设计/实现。^0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|N|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|O|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|P|9|@]|A|@]|B|$]]|$2|G|4|H|6|I|8|Q|9|@]|A|@]|B|$J|K]]|$2|L|4|M|6|7|8|R|9|@]|A|@]|B|$]]]]

I also received this error while writing a custom form control component in Angular 7. However, none of the answers are applicable to Angular 7.

In my case, the following needed to be add to the <code>@Component</code> decorator:

<pre><code> providers: [
 {
 provide: NG_VALUE_ACCESSOR,
 useExisting: forwardRef(() =&gt; MyCustomComponent), // replace name as appropriate
 multi: true
 }
 ]
</code></pre>

This is a case of "I don't know why it works, but it does." Chalk it up to poor design/implementation on the part of Angular.

entityMap|blocks|key|cl4kp|text|我也有同样的错误，angular+7|type|unstyled|depth|inlineStyleRanges|entityRanges|data|d4hct|{{city.name}}|code-block|syntax|javascript|5cmpo|我刚添加了|d1p6k|ngDefaultControl|fnm3c^0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|M|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|N|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|O|9|@]|A|@]|B|$]]|$2|J|4|K|6|7|8|P|9|@]|A|@]|B|$]]|$2|L|4|D|6|E|8|Q|9|@]|A|@]|B|$F|G]]]]

I also had the same error , angular 7

<pre><code> &lt;button (click)="Addcity(city.name)" [(ngModel)]="city.name" class="dropdown-item fontstyle"
 *ngFor="let city of Cities; let i = index"&gt;
 {{city.name}}
 &lt;/button&gt;
</code></pre>

I just added ngDefaultControl

<pre><code> &lt;button (click)="Addcity(city.name)" [(ngModel)]="city.name" ngDefaultControl class="dropdown-item fontstyle"
 *ngFor="let city of Cities; let i = index"&gt;
 {{city.name}}
</code></pre>

entityMap|blocks|key|d79g0|text|我也犯了同样的错误--我不小心绑定了|type|unstyled|depth|inlineStyleRanges|entityRanges|data|245to|(ngModel)|97ofb|致我的|67apq|而不是|3da86|元素。^0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|K|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|L|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|M|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|N|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|O|9|@]|A|@]|B|$]]]]

I had this same error- I accidentally binded [(ngModel)] to my <code>mat-form-field</code> instead of the <code>input</code> element.

entityMap|blocks|key|h24f|text|在我的例子中，我使用了指令，但没有将它导入到我的module.ts文件中。导入修复了它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data^0^^$0|$]|1|@$2|3|4|5|6|7|8|C|9|@]|A|@]|B|$]]]]

In my case i used directive, but hadn't imported it in my module.ts file. Import fixed it.

entityMap|blocks|key|8o7q7|text|在我的例子中，我插入了|type|unstyled|depth|inlineStyleRanges|entityRanges|data|bq235|(ngModel)|ed5ip|在标签上而不是输入上。还有一个警告，我试着在指定的行中正确地运行上面的错误，但是错误不会出现。如果您在其他地方犯了相同的错误，它仍然会在同一行抛出相同的错误^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|G|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|H|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|I|9|@]|A|@]|B|$]]]]

In my case, I had inserted [(ngModel)] on label rather than input.
There is also a caveat, I tried running after correctly the above error in the specified line but the error wouldn't go. If there are other places where you have committed the same mistake, it still throws you the same error at the same line

entityMap|blocks|key|fn7c1|text|我也有同样的错误，但在我的例子中，很明显是在呈现组件html的时候出现了同步问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|bpon7|我遵循了这个页面上提出的一些解决方案，但它们中的任何一个都对我有效，至少不是完全有效。|cuk4i|实际上解决了我的错误的方法是在元素的父html标记中编写下面的代码片段。|bbibh|我正在绑定变量。|9csh6|代码：|68nmr|*ngIf="variable-name"|code-block|syntax|javascript|c94ae|错误是由项目试图渲染页面引起的，显然在计算变量的时候，项目就是找不到它的值。使用上面的代码片段，您要确保在呈现页面之前询问变量是否已初始化。|esoti|这是我的component.ts代码：|eu69u|import+{+Component,+OnInit+}+from+'@angular/core';
import+{+InvitationService+}+from+'src/app/service/invitation.service';
import+{+BusinessService+}+from+'src/app/service/business.service';
import+{+Invitation+}+from+'src/app/_models/invitation';
import+{+forEach+}+from+'@angular/router/src/utils/collection';

@Component({
++selector:+'app-invitation-details',
++templateUrl:+'./invitation-details.component.html',
++styleUrls:+['./invitation-details.component.scss']
})
export+class+InvitationDetailsComponent+implements+OnInit+{
++invitationsList:+any;
++currentInvitation:+any;
++business:+any;
++invitationId:+number;
++invitation:+Invitation;

++constructor(private+InvitationService:+InvitationService,+private+BusinessService:+
BusinessService)+{+
this.invitationId+=+1;+//prueba+temporal+con+invitacion+1
this.getInvitations();
this.getInvitationById(this.invitationId);
++}

+++ngOnInit()+{

++}

++getInvitations()+{
++++this.InvitationService.getAllInvitation().subscribe(result+=>+{
++++++this.invitationsList+=+result;
++++++console.log(result);
++++},+error+=>+{
++++++console.log(JSON.stringify(error));
++++});
++}

++getInvitationById(invitationId:number){
++++this.InvitationService.getInvitationById(invitationId).subscribe(result+=>+{
++++++this.currentInvitation+=+result;
++++++console.log(result);
++++++//this.business=this.currentInvitation['business'];
+++++++//console.log(this.currentInvitation['business']);+
+++++},+error+=>+{
+++++console.log(JSON.stringify(error));
++++});
++}
++++++...|fttni|下面是我的html标记：|k9he|...


I+hope+this+can+be+helpful.^0|0|0|0|0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|Z|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|10|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|11|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|12|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|13|9|@]|A|@]|B|$]]|$2|K|4|L|6|M|8|14|9|@]|A|@]|B|$N|O]]|$2|P|4|Q|6|7|8|15|9|@]|A|@]|B|$]]|$2|R|4|S|6|7|8|16|9|@]|A|@]|B|$]]|$2|T|4|U|6|M|8|17|9|@]|A|@]|B|$N|O]]|$2|V|4|W|6|7|8|18|9|@]|A|@]|B|$]]|$2|X|4|Y|6|M|8|19|9|@]|A|@]|B|$N|O]]]]

I had the same error, but in my case apparently it was a synchronization issue, at the moment of render the components html.

I followed some of the solutions proposed on this page but any of them worked for me, at least not completely. 

What did actually solve my error was to write the below code snippet inside the father html tag of the elements .

I was binding to the variable.

Code:

<pre><code> *ngIf="variable-name"
</code></pre>

The error was caused, apparently by the project trying to render the page, apparently at the moment of evaluating the variable, the project just could no find its value. With the above code snippet you make sure that before rendering the page you ask if the variable has being initialized.

This is my component.ts code:

<pre><code>import { Component, OnInit } from '@angular/core';
import { InvitationService } from 'src/app/service/invitation.service';
import { BusinessService } from 'src/app/service/business.service';
import { Invitation } from 'src/app/_models/invitation';
import { forEach } from '@angular/router/src/utils/collection';

@Component({
 selector: 'app-invitation-details',
 templateUrl: './invitation-details.component.html',
 styleUrls: ['./invitation-details.component.scss']
})
export class InvitationDetailsComponent implements OnInit {
 invitationsList: any;
 currentInvitation: any;
 business: any;
 invitationId: number;
 invitation: Invitation;

 constructor(private InvitationService: InvitationService, private BusinessService: 
BusinessService) { 
this.invitationId = 1; //prueba temporal con invitacion 1
this.getInvitations();
this.getInvitationById(this.invitationId);
 }

 ngOnInit() {

 }

 getInvitations() {
 this.InvitationService.getAllInvitation().subscribe(result =&gt; {
 this.invitationsList = result;
 console.log(result);
 }, error =&gt; {
 console.log(JSON.stringify(error));
 });
 }

 getInvitationById(invitationId:number){
 this.InvitationService.getInvitationById(invitationId).subscribe(result =&gt; {
 this.currentInvitation = result;
 console.log(result);
 //this.business=this.currentInvitation['business'];
 //console.log(this.currentInvitation['business']); 
 }, error =&gt; {
 console.log(JSON.stringify(error));
 });
 }
 ...
</code></pre>

Here is my html markup:

<pre><code>&lt;div class="container-fluid mt--7"&gt;
 &lt;div class="row"&gt;
 &lt;div class="container col-xl-10 col-lg-8"&gt;
 &lt;div class="card card-stats "&gt;
 &lt;div class="card-body container-fluid form-check-inline" 
 *ngIf="currentInvitation"&gt;
 &lt;div class="col-4"&gt;
 ...
</code></pre>

I hope this can be helpful.

entityMap|blocks|key|4f8li|text|我遇到了同样的错误，我有一个输入字段，名为|type|unstyled|depth|inlineStyleRanges|entityRanges|data|enpea|在我的自定义窗体组件中，但是意外地在名为的输入中传递了控制|d83gj|..。希望没有人面临这个问题。^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|G|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|H|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|I|9|@]|A|@]|B|$]]]]

I had this same error, I had a input field named <code>control</code> in my custom Form Component but was accidentally passing control in input named <code>formControl</code>. Hope no one faces that issue.

entityMap|blocks|key|9kiqr|text|我在运行Karma单元测试用例时遇到了这个错误|type|unstyled|depth|inlineStyleRanges|entityRanges|data|c34hp|MatSelectModule|5ijtk|在导入中修复问题|f2l30|imports:+[
++++++++HttpClientTestingModule,
++++++++FormsModule,
++++++++MatTableModule,
++++++++MatSelectModule,
++++++++NoopAnimationsModule
++++++],|code-block|syntax|javascript^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|M|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|N|9|@]|A|@]|B|$]]|$2|G|4|H|6|I|8|O|9|@]|A|@]|B|$J|K]]]]

I was facing this error while running Karma Unit Test cases 
Adding MatSelectModule in the imports fixes the issue

<pre><code>imports: [
 HttpClientTestingModule,
 FormsModule,
 MatTableModule,
 MatSelectModule,
 NoopAnimationsModule
 ],
</code></pre>

entityMap|blocks|key|fv69p|text|你有没有试过移动你的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|lqhu|到|4ors3|而不是|5ekh0|在你的HTML里？我在我的代码中出现了同样的错误，这是因为我将模型绑定到a而不是a。虽然我没有使用表单控件。^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|I|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|J|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|K|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|L|9|@]|A|@]|B|$]]]]

Have you tried moving your <code>[(ngModel)]</code> to the <code>div</code> instead of the <code>switch</code> in your HTML? I had the same error appear in my code and it was because I bound the model to a <code>&lt;mat-option&gt;</code> instead of a <code>&lt;mat-select&gt;</code>. Though I am not using form control.

entityMap|blocks|key|4ddk0|text|在我的例子中，它是一个不存在的component.member，例如|type|unstyled|depth|inlineStyleRanges|entityRanges|data|57c55|[formControl]="personId"|code-block|syntax|javascript|b8ufv|将其添加到类声明中可以修复它|8oj0i|this.personId+=+new+FormControl(...)^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|M|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|N|9|@]|A|@]|B|$]]|$2|J|4|K|6|E|8|O|9|@]|A|@]|B|$F|G]]]]

In my case it was a component.member which was not existing e.g.

<pre><code>[formControl]="personId"
</code></pre>

Adding it to the class declaration fixed it

<pre><code>this.personId = new FormControl(...)
</code></pre>

entityMap|blocks|key|e1mld|text|我在使用Jasmine进行单元测试时收到了这个错误消息。我添加了|type|unstyled|depth|inlineStyleRanges|entityRanges|data|ac2n9|ngDefaultControl|dk23e|属性添加到自定义元素(在我的例子中，它是一个角度材质滑动切换)，这样就解决了这个错误。|e5s47|Extra+Cheese|code-block|syntax|javascript|b65iv|更改上面的元素以包含|3nbpr|epqcb|属性|rmhc|Extra+Cheese^0|0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|S|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|T|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|U|9|@]|A|@]|B|$]]|$2|G|4|H|6|I|8|V|9|@]|A|@]|B|$J|K]]|$2|L|4|M|6|7|8|W|9|@]|A|@]|B|$]]|$2|N|4|D|6|7|8|X|9|@]|A|@]|B|$]]|$2|O|4|P|6|7|8|Y|9|@]|A|@]|B|$]]|$2|Q|4|R|6|I|8|Z|9|@]|A|@]|B|$J|K]]]]

I was getting this error message in my Unit tests with Jasmine. I added ngDefaultControl attribute to the custom element(in my case it was an angular material slide toggle) and this resolves the error.

<pre><code>&lt;mat-slide-toggle formControlName="extraCheese"&gt;
 Extra Cheese
&lt;/mat-slide-toggle&gt;
</code></pre>

Change the above element to include ngDefaultControl atttribute

<pre><code>&lt;mat-slide-toggle ngDefaultControl formControlName="extraCheese"&gt;
 Extra Cheese
&lt;/mat-slide-toggle&gt;
</code></pre>

entityMap|blocks|key|6h1kh|text|在我的例子中，我有一个|type|unstyled|depth|inlineStyleRanges|entityRanges|data^0^^$0|$]|1|@$2|3|4|5|6|7|8|C|9|@]|A|@]|B|$]]]]

in my case, I had a <code>&lt;TEXTAREA&gt;</code> tag from old html while converting to angular. Had to change to <code>&lt;textarea&gt;</code>.

entityMap|blocks|key|8i7t9|text|在我的例子中，它就像在我的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|86jqg|声明|f33fu|注释|6ss6l|在出口方面。^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|I|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|J|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|K|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|L|9|@]|A|@]|B|$]]]]

In my case it was as daft as having registered the new component for DI in my <code>app.module.ts</code> declarations but not in exports.

entityMap|blocks|key|2ibrt|text|在我的例子中，错误是通过复制模块中组件的导入而触发的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data^0^^$0|$]|1|@$2|3|4|5|6|7|8|C|9|@]|A|@]|B|$]]]]

In my case, the error was triggered by duplicating an import of a component in the module.

entityMap|blocks|key|99e8u|text|#背景|type|unstyled|depth|inlineStyleRanges|entityRanges|data|31v4l|NativeScript+6.0|216s|在我的例子中，这个错误是通过将元素标记从改为by+fault而触发的。内部|194kd|删除后|4m57n|(ngModel)|c5epp|="name“错误已消失。^0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|M|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|N|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|O|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|P|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|Q|9|@]|A|@]|B|$]]|$2|K|4|L|6|7|8|R|9|@]|A|@]|B|$]]]]

#Background
<ul>
<li>NativeScript 6.0</li>
</ul>
In my case, the error was triggered by changing element tag from to by fault. Inside &lt;TextView an [(ngModel)]=&quot;name&quot;. was defined.
After removing [(ngModel)]=&quot;name&quot; error was gone.

entityMap|blocks|key|di4vm|text|我在运行单元测试时遇到了这个问题。为了解决这个问题，我在spect.ts文件的导入中添加了MatSlideToggleModule。|type|unstyled|depth|inlineStyleRanges|entityRanges|data^0^^$0|$]|1|@$2|3|4|5|6|7|8|C|9|@]|A|@]|B|$]]]]

I was facing this issue while running unit tests. To fix I added the MatSlideToggleModule to the imports in my spec.ts file.

entityMap|blocks|key|b87iu|text|当我将我的一个组件输入命名为'formControl‘时，我也收到了这个错误。它可能是为别的东西预留的。如果你想在组件之间传递FormControl对象，可以这样使用它：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1gunq|@Input()+control:+FormControl;|code-block|syntax|javascript|21lk9|不是这样的：|75si9|@Input()+formControl:+FormControl;|evn86|奇怪-但工作正常:)^0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|N|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|O|9|@]|A|@]|B|$F|G]]|$2|H|4|I|6|7|8|P|9|@]|A|@]|B|$]]|$2|J|4|K|6|E|8|Q|9|@]|A|@]|B|$F|G]]|$2|L|4|M|6|7|8|R|9|@]|A|@]|B|$]]]]

I also received this error when I named one of my component inputs 'formControl'. Probably it's reserved for something else. If you want to pass FormControl object between components, use it like that:
<pre><code>@Input() control: FormControl;
</code></pre>
not like this:
<pre><code>@Input() formControl: FormControl;
</code></pre>
Weird - but working :)

entityMap|blocks|key|50ku1|text|如果您尝试将ngModel添加到非输入元素中，也会发生此错误。确保只将ngModel添加到标记中。在我的例子中，我向中添加了一个ngModel，而不是。|type|unstyled|depth|inlineStyleRanges|entityRanges|data^0^^$0|$]|1|@$2|3|4|5|6|7|8|C|9|@]|A|@]|B|$]]]]

This error also occurs if you try to add ngModel to the non-input elements like <code>&lt;option&gt;</code> HTML tags. Make sure you add ngModel only to the <code>&lt;input&gt;</code> tags.
In my case, I have added a ngModel to the <code>&lt;ion-select-option&gt;</code> instead of <code>&lt;ion-select&gt;</code>.

entityMap|blocks|key|d98s4|text|在我的例子中，我忘记添加|type|unstyled|depth|inlineStyleRanges|entityRanges|data|c7jro|添加到我的自定义组件|enbu|我有输入|iudm|_|6sbqj|价值|cj1v8|ff952|访问器创建为：|7j69d|export+const+INPUT_VALUE_ACCESSOR+=+{
++provide:+NG_VALUE_ACCESSOR,
++useExisting:+forwardRef(()+=>+TextEditorComponent),
++multi:+true,
};|code-block|syntax|javascript^0|0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|S|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|T|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|U|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|V|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|W|9|@]|A|@]|B|$]]|$2|K|4|H|6|7|8|X|9|@]|A|@]|B|$]]|$2|L|4|M|6|7|8|Y|9|@]|A|@]|B|$]]|$2|N|4|O|6|P|8|Z|9|@]|A|@]|B|$Q|R]]]]

In my case I forgot to add <code>providers: [INPUT_VALUE_ACCESSOR]</code> to my custom component
I had INPUT_VALUE_ACCESSOR created as:
<pre><code>export const INPUT_VALUE_ACCESSOR = {
 provide: NG_VALUE_ACCESSOR,
 useExisting: forwardRef(() =&gt; TextEditorComponent),
 multi: true,
};
</code></pre>

entityMap|blocks|key|7v71i|text|在我的例子中，问题是我创建了一个|type|unstyled|depth|inlineStyleRanges|entityRanges|data|aenuu|具有保留名称的变量|49b6b|..。^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|G|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|H|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|I|9|@]|A|@]|B|$]]]]

In my case the problem was that i created an <code>@Input</code> variable with the reserved name <code>formControl</code>.

Here is my Angular component:
<pre class="lang-ts prettyprint-override"><code>@Component( {
 selector: 'input-extra-field',
 template: `
 &lt;div class=&quot;form-group&quot; [formGroup]=&quot;formGroup&quot; &gt;
 &lt;switch [attr.title]=&quot;field.etiquette&quot; 
 [attr.value]=&quot;field.valeur&quot; [(ngModel)]=&quot;field.valeur&quot;
 [formControl]=&quot;fieldControl&quot; [attr.id]=&quot;name&quot; [attr.disabled]=&quot;disabled&quot;&gt;
 &lt;/switch&gt;
 &lt;error-messages [control]=&quot;name&quot;&gt;&lt;/error-messages&gt;
 &lt;/div&gt;
 `
} )
</code></pre>
Here is my Class:
<pre class="lang-ts prettyprint-override"><code>export class SwitchExtraField extends ExtraField {
 @Input() field: ExtraFormField;
 @Input() entity: { fields: Object };
 @Input() formGroup: FormGroup;

 constructor( formDir: NgForm ) {
 super( null, null, formDir );
 }

 get disabled(): string {
 if ( this.field &amp;&amp; !!this.field.saisissable &amp;&amp; !this.field.saisissable ) {
 return 'disabled';
 }
 return null;
 }
}
</code></pre>
This is the error I get when compiling:
<pre class="lang-none prettyprint-override"><code>ERROR Error: No value accessor for form control with unspecified name attribute
 at _throwError (forms.es5.js:1918)
 at setUpControl (forms.es5.js:1828)
 at FormControlDirective.webpackJsonp.../../../forms/@angular/forms.es5.js.FormControlDirective.ngOnChanges (forms.es5.js:4617)
</code></pre>
When I change the element switch to input it works, knowing that I'm using the same structure to other components and it works fine.

ERROR Error: No value accessor for form control with unspecified name attribute on switch

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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 这是我的Angular组件： @Component( {    selector: 'input-extra-field',    template: `                                                                            `} ) 这...

问错误错误:开关上具有未指定名称属性的表单控件没有值访问器
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问错误错误:开关上具有未指定名称属性的表单控件没有值访问器EN