TypeScript. FormGroup FormArray - remove only one element object by value. Angular 2 4

this.formGroup = this.formBuilder.group({
images: this.fb.array([])
});

I add new element in this way: this.images.push(new FormControl(new ImageCreateForm(this.imageResponse.id)));

get images(): FormArray {
return <FormArray>this.formGroup.controls.images;
}

My classes:

export class ImageCreateForm {
id: number;
constructor(id: number) {
this.id = id;
}
}


export class ImageResponse {
id: number;
url: string;
}

When I added images, then my {{ formGroup.value | json }} is:

"images": [
{
"id": 501
},
{
"id": 502
},
{
"id": 503
}
]

I want to remove images (for example only image with id=502) from formGroup before when I send my form POST request. Is it possible? I tried use reset method, but this remove all elements: this.images.reset({"id":image.id});. Where image it is a ImageResponse object.

Result: {"images": [ null, null, null ]}, but I want:

"images": [
{
"id": 501
},
{
"id": 503
}
]

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小开

最佳答案

FormArray class has removeAt which takes the index. If you do not know the index, you can do a workaround:

this.images.removeAt(this.images.value.findIndex(image => image.id === 502))

小开

In Angular Reactive Forms, formArray has a method called removeAt(). You can use it by passing an index that you want to delete:

delete(index){
this.array.removeAt(index)
}
``

小开

if you want to remove a value for a particular Key from the FormGroup, You can use following code -

this.formGroupF.controls[value].patchValue(null)