How to update multiple rows in the table? Angular 7

Question

In my project there is popup which contain multiple values in loop.

Every row contains Enable button which convert text into text boxes and in the end of page there is a button name "Update".Then all the enable rows values are goes as a API parameter and then update al the rows. This below page have same functionality but this is in angular js. https://embed.plnkr.co/plunk/2Fue9L

Answer 1

A very simple formArray. As always we have a function that creates the formGroup and some auxiliary variables

  editing: number = -1; //<--here store the row we are editing
                        //typically we initialize the variable with "-1"
                        //to say that there are no rows selected
  formArray: FormArray = new FormArray([]); //<--our formArray, 
        //At first is empty, but NOT null, see =new FormArray([])
  oldValue: any; //<--here store the old values, this allows us
       //recover the data if we cancel the editing

createGroup() {
    return new FormGroup({
      prop1: new FormControl(),
      prop2: new FormControl(),
      prop3: new FormControl()
    });
  }

And a function to edit, cancel and add another row

edit(index: number) {  //we pass the "index" of the row we want to edit
    this.editing = index;
    this.oldValue = {  //here store the actual value
                       //we using "spread operator"
                       //yes, we need a copy of the old values
      ...this.formArray.at(index).value
    };
  }

  cancel() {  //we using the oldValue to 
    this.formArray.at(this.editing).setValue(this.oldValue);
    this.editing=-1;  //and there are no row editing
  }

  add() //simple "push" a formGroup in our array
  {
    this.formArray.push(this.createGroup())
    //I say that, when add a new row we want beging to edit it
    this.edit(this.formArray.controls.length-1)
  }

A simple (and very ugly .html)

<button (click)="add()">Add</button>
<form [formGroup]="formArray" (submit)="submit(formArray)">
  <table>
    <tr>
      <th>Prop1</th>
      <th>Prop2</th>
      <th>Prop3</th>
    </tr>
    <tbody>
     <!--we using ng-container to not create additional "tags"-->
     <!-- see how manage a formArray using let "group" of...
          and [formGroup]="group"
     -->
    <ng-container *ngFor="let group of formArray.controls;let i=index" [formGroup]="group">
       <!--when we are editing, show the inputs-->
        <tr *ngIf="editing==i"> 
      <th>
            <input formControlName="prop1">
      </th>
      <th>
            <input formControlName="prop2">
      </th>
      <th>
            <input formControlName="prop3">
      </th>
      <th>
            <button (click)="editing=-1">OK</button>
            <button (click)="cancel()">Cancel</button>
      </th>
        </tr>
       <!--when we are NOT editing, show the values-->
        <tr *ngIf="editing!=i">
      <td>
            {{group.get('prop1').value}}
      </td>
      <td>
            {{group.get('prop2').value}}
      </td>
      <td>
            {{group.get('prop3').value}}
      </td>
      <td>
            <button (click)="edit(i)">Edit</button>
            <button (click)="formArray.removeAt(i)">Delete</button>
      </td>
        </tr>
    </ng-container>
  </tbody>
  </table>
  <button>submit</button>
</form>

The function submit

submit(formArray) {
    if (formArray.valid)
    {
       this.myService.saveData(formArray.value).  //(*)
          subscribe(res=>{
             console.log(res)
          })
    }
    else 
       this.formArray.markAllAsTouched();
  }


//(*)I has a service with a simple

saveData(data:any[])
{
    return this.httpClient.post("http://....",data)
}

And the stackblitz

The API can be, if you're using .NET Core

public class Data
{
    string prop1 {get;set;}
    string prop2 {get;set;}
    string prop3 {get;set;}
}

[HttpPost), ActionName("UpdateBulk")]
public async Task<object> UpdateBulk([FromBody]Data[]){
   try{
    ..you save your data here...
    return Ok(new { success = true, errorText = "Data saved!" });
   }
   catch(){
    return Ok(new { success = false, errorText = "Data incorrect" });
   }
}