table em angular

1<ng-container matColumnDef="select">
2  <th mat-header-cell *matHeaderCellDef>
3    <mat-checkbox (change)="$event ? masterToggle() : null"
4                  [checked]="selection.hasValue() && isAllSelected()"
5                  [indeterminate]="selection.hasValue() && !isAllSelected()">
6    </mat-checkbox>
7  </th>
8  <td mat-cell *matCellDef="let row">
9    <mat-checkbox (click)="$event.stopPropagation()"
10                  (change)="$event ? selection.toggle(row) : null"
11                  [checked]="selection.isSelected(row)">
12    </mat-checkbox>
13  </td>
14</ng-container>
15