问题描述
假设我有以下表单结构:
let's say I have the following form structure:
this.myForm = this.formBuilder.group({
date: ['', [Validators.required]],
notes: [''],
items: this.initItems()
});
initItems() {
var formArray = this.formBuilder.array([]);
for (let i = 0; i < 2; i++) {
formArray.push(this.formBuilder.group({
name: ['', [Validators.required]],
age: ['', [Validators.required]],
}));
}
return formArray;
}
并且名称控件应该是自动完成的,我如何将所有名称控件与自动完成列表相关联?
and the name control supposed to be an autocomplete, how can I relate the all the name controls to an autocomplete list?
推荐答案
我通过将 FormArray
中的每个 name
控件关联到一个 filteredOption数组:
I solved this by relating each
name
control inside the FormArray
to a filteredOption
array:
ManageNameControl(index: number) {
var arrayControl = this.myForm.get('items') as FormArray;
this.filteredOptions[index] = arrayControl.at(index).get('name').valueChanges
.pipe(
startWith<string | User>(''),
map(value => typeof value === 'string' ? value : value.name),
map(name => name ? this._filter(name) : this.options.slice())
);
}
然后每次我在
form Array
中构建一个 formgroup
之后(创建新项目),我需要像这样在新索引处调用上面的函数:
Then After each time I build a
formgroup
inside the form Array
(create new item), I need to call the above function at the new index like this:
addNewItem() {
const controls = <FormArray>this.myForm.controls['items'];
let formGroup = this.formBuilder.group({
name: ['', [Validators.required]],
age: ['', [Validators.required]],
});
controls.push(formGroup);
// Build the account Auto Complete values
this.ManageNameControl(controls.length - 1);
}
在.html文件中,我们需要引用所需的filteredOption数组,我们可以通过使用
i
索引来实现:
In the .html file, we need to refer to the desired filteredOption array, we can do this by using the
i
index:
<mat-option *ngFor="let option of filteredOptions[i] | async " [value]="option">
{{ option.name }}
</mat-option>
请在此处查看详细答案https://stackblitz.com/edit/angular-szxkme?file=app%2Fautocomplete-display-example.ts
更新:要使用特定对象的默认值填充数组,您可以使用如下接收表单:
Update:to populate the array with a default value for a specific object, you can do it using the receive forms like this:
let formGroup = this.fb.group({
name: [{value: { name: 'Mary' } , disabled: false}, [Validators.required]],
age: ['', [Validators.required]],
});
这篇关于如何在 FormArray (Reactive Forms) 中使用 mat-autocomplete (Angular Material Autocomplete)的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!