Angular 5 FormArray

Question

我的 Angular 5/Angular Material 应用程序中有这个 FormArray:

this.form = new FormGroup({    
    customerNumberContainers: new FormArray([
      new FormGroup({
        contactTenant: new FormControl('', [Validators.required, Validators.minLength(2)]),
        customerNumber: new FormControl('', [Validators.required, Validators.minLength(2)])
        }),
    ]),
...

其实我不知道如何跑遍这个FormArray。 我试过这个

<form [formGroup]="form" (ngSubmit)="onSubmit()">
    <div formGroupName="customerNumberContainers">          
        <div *ngFor="let customerNumberContainer of form.controls['customerNumberContainers']; index as i">
            <mat-input-container class="full-width-input" style="min-width:100px;">
                 <input matInput placeholder="Tenant" formControlName="customerNumberContainer[i].contactTenant">
            </mat-input-container> 
            <mat-input-container class="full-width-input" style="min-width:100px;">
                 <input matInput placeholder="Customernumber" formControlName="customerNumberContainer[i].customerNumber">
            </mat-input-container> 
        </div>
    </div>
   ...

Answer 1

实际上你应该怎么做:

有一个返回你的控件数组的方法

get customerNumberContainers(): FormArray {
    return this.form.get("customerNumberContainers") as FormArray;
    } 

您将使用变量i 来管理数组中的表单组

<form [formGroup]="form" (ngSubmit)="onSubmit()">
<div formArrayName="customerNumberContainers">          
    <div *ngFor="let customerNumberContainer of customerNumberContainers.controls; index as i" [formGroupName]="i">
        <mat-input-container class="full-width-input" style="min-width:100px;">
             <input matInput placeholder="Tenant" formControlName="contactTenant">
        </mat-input-container> 
        <mat-input-container class="full-width-input" style="min-width:100px;">
             <input matInput placeholder="Customernumber" formControlName="customerNumber">
        </mat-input-container> 
    </div>
</div>

...

您可以创建添加方法和删除方法来管理数组中的表单组

add(data?: any) {
   /// data is to set up values to your internal form (useful for edition)
        this.customerNumberContainers.push(this.fb.group({
         }))
    }

    remove(index: number) {
        this.customerNumberContainers.removeAt(index)
    }

希望对你有帮助

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