我正在处理angular2应用程序,并且在表单字段中存储多个复选框的值时遇到问题。
输入脚本
form : FormGroup;
cities = ["Mohali", "Chandigarh", "Ludhiana", "Amritsar"];
zip_codes = ["282001", "456123", "123456", "140412"];
constructor(private formBuilder : FormBuilder)
{
this.form = this.formBuilder.group({
cities : this.formBuilder.array(["Mohali", "Amritsar"]),
zip_codes : this.formBuilder.array(["456123"])
});
}
HTML
<div *ngFor="let city of cities">
<input type="checkbox" formControlName="cities" value="city">
<span>{{city}}</span>
</div>
<div *ngFor="let zipCode of zip_codes">
<inbput type="checkbox" formControlName="zip_codes" value="zipCode">
<span>{{zipCode}}</span>
</div>
我想在表单字段中存储已检查的城市和zip_codes,当我在表单字段中有默认值时,将自动检查数组中的值。
答案 0 :(得分:11)
一种方式是这样的:
1)使用FormArray
默认值设置false
字段
this.form = this.formBuilder.group({
cities : this.formBuilder.array(this.cities.map(x => !1)),
zip_codes : this.formBuilder.array(this.zip_codes.map(x => !1))
});
2)模板如下所示:
<div *ngFor="let city of cities; let i = index" formArrayName="cities">
<input type="checkbox" [formControlName]="i">
<span>{{city}}</span>
</div>
<div *ngFor="let zipCode of zip_codes; let i = index" formArrayName="zip_codes">
<input type="checkbox" [formControlName]="i">
<span>{{zipCode}}</span>
</div>
3)提交表格
convertToValue(key: string) {
return this.form.value[key].map((x, i) => x && this[key][i]).filter(x => !!x);
}
onSubmit() {
const valueToStore = Object.assign({}, this.form.value, {
cities: this.convertToValue('cities'),
zip_codes: this.convertToValue('zip_codes')
});
console.log(valueToStore);
}
4)默认值
const defaultCities = ["Mohali", "Amritsar"];
const defaultZipCodes = ["456123"];
this.form = this.formBuilder.group({
cities: this.formBuilder.array(this.cities.map(x => defaultCities.indexOf(x) > -1)),
zip_codes: this.formBuilder.array(this.zip_codes.map(x => defaultZipCodes.indexOf(x) > -1))
});
<强> Plunker Example 强>
答案 1 :(得分:1)
我非常喜欢@yurzui的答案 但有一个问题,让价值回来..所以......
我的解决方案 - 使用Material View解决了Angular 5的问题 连接是通过
formArrayName =&#34;通知&#34;
(更改)=&#34; updateChkbxArray(n.id,$ event.checked,&#39;通知&#39;)&#34;
这样它可以在一个表单中用于多个复选框数组。 只需设置每次连接的控件数组的名称。
constructor(
private fb: FormBuilder,
private http: Http,
private codeTableService: CodeTablesService) {
this.codeTableService.getnotifications().subscribe(response => {
this.notifications = response;
})
...
}
createForm() {
this.form = this.fb.group({
notification: this.fb.array([])...
});
}
ngOnInit() {
this.createForm();
}
updateChkbxArray(id, isChecked, key) {
const chkArray = < FormArray > this.form.get(key);
if (isChecked) {
chkArray.push(new FormControl(id));
} else {
let idx = chkArray.controls.findIndex(x => x.value == id);
chkArray.removeAt(idx);
}
}
&#13;
<div class="col-md-12">
<section class="checkbox-section text-center" *ngIf="notifications && notifications.length > 0">
<label class="example-margin">Notifications to send:</label>
<p *ngFor="let n of notifications; let i = index" formArrayName="notification">
<mat-checkbox class="checkbox-margin" (change)="updateChkbxArray(n.id, $event.checked, 'notification')" value="n.id">{{n.description}}</mat-checkbox>
</p>
</section>
</div>
&#13;
很高兴有任何改进的评论。
以下是Gist