And*_*rra 5 angular angular-forms
我有两个单选按钮组,我向其中添加了角度形式控件。我遇到的问题是,当我添加控件时,单选按钮分组消失了。此外,当我检查单选按钮时,它的name属性也消失了。结果是我无法再在不同的单选按钮组之间正确切换。我怎样才能解决这个问题?
示例: https: //stackblitz.com/edit/angular-qdqnmo
TS:
import { Component, OnInit } from '@angular/core';
import { FormControl, FormGroup } from '@angular/forms';
@Component({
selector: 'my-app',
templateUrl: './app.component.html',
styleUrls: [ './app.component.css' ]
})
export class AppComponent implements OnInit {
formData = {
"questions": [
{
"refCode": "Question1",
"answers": [
{
"refCode": "Question1Answer1",
"selected": true
},
{
"refCode": "Question1Answer2",
"selected": false
}
]
},
{
"refCode": "Question2",
"answers": [
{
"refCode": "Question2Answer1",
"selected": false
},
{
"refCode": "Question2Answer2",
"selected": false
},
{
"refCode": "Question3Answer3",
"selected": true
}
]
}
]
};
formGroup: FormGroup;
ngOnInit() {
const group = {};
this.formData.questions.forEach(question => {
group[question.refCode] = new FormControl();
});
this.formGroup = new FormGroup(group);
}
}
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HTML:
<h2>Normal Buttons:</h2>
<div *ngFor="let question of formData.questions; index as i;">
<h3>Group {{i + 1}}:</h3>
<div>
<div *ngFor="let answer of question.answers" >
<input type="radio" id="answer.refCode" [checked]="answer.selected"
[name]="question.refCode" [value]="answer.refCode" >
<label for="answer.refCode">{{answer.refCode}}</label>
</div>
</div>
--------------------------------------------------------------------
</div>
<h2>Angular Buttons:</h2>
<div *ngFor="let question of formData.questions; index as i;">
<h3>Group {{i + 1}}:</h3>
<div [formGroup]="formGroup">
<div *ngFor="let answer of question.answers" >
<input type="radio" id="answer.refCode" [checked]="answer.selected"
[name]="question.refCode" [value]="answer.refCode"
[formControlName]="question.refCode">
<label for="answer.refCode">{{answer.refCode}}</label>
</div>
</div>
--------------------------------------------------------------------
</div>
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模块:
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { AppComponent } from './app.component';
@NgModule({
imports: [ BrowserModule, FormsModule, ReactiveFormsModule ],
declarations: [ AppComponent ],
bootstrap: [ AppComponent ]
})
export class AppModule { }
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题外话:有趣的问题,以前没有注意到这一点!
使用属性绑定而不是属性绑定似乎可以解决这个问题!这样您就可以获得name字段中的实际属性,就像“普通”按钮一样。
但是......您还有另一个即将出现的问题,所以让我们也解决这个问题,无论如何您最终都会遇到这个问题。
但首先,使用属性绑定:
使用:
[attr.name]="question.refCode"
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代替:
[name]="question.refCode"
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然后谈谈你的另一个问题。当然,在模板中使用时[checked],它看起来已检查,但实际上,直到您与单选按钮交互时才会设置表单值。因此,删除[checked]并将值设置为表单控件。这意味着您正在寻找selected属性为true(如果存在)的答案,但您想将其用作refCode值。那么我建议如下:
this.formData.questions.forEach(question => {
const preselected = question.answers.find(x => x.selected === true)
group[question.refCode] = new FormControl((preselected && preselected.refCode) || null);
});
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