toggle checkbox Angular 2

Question

Hi am using angular 2 data-table in my project.

my tbody:

<tbody>
        <tr *ngFor="let item of main.data; let ndx = index">
            <td>
                <mfRowSelector [checkboxId]="ndx"
                                [entity]="item" (change)="toggleItem(item)" (selectEntity)="main.addRemoveSelectedEntity($event)"
                                >
                </mfRowSelector>
            </td>
            <td class="no-wrap">{{item.date | date}}</td>
            <td class="no-wrap">{{item.currency}}</td>
            <td class="no-wrap">{{item.amount | number:'.2-2'}}</td>
            <td>
                <input type="text" [(ngModel)]="item.amountEntered">
            </td>
        </tr>
    </tbody>

When I select rows, selectEntity will pass the selected rows as an array. So if i select multiple i'll get an array of multiple objects. As above i have an input field, on checkbox select the value in amount td will copied over to input field. Until here is working. The problem is how I can reset this value on un-select the checkbox? Any idea guys? Thanks in advance.

My Function:

selectedRows(selectedRows: any) {
    selectedRows.map(obj => {
        obj.amountEntered = obj.amount;
        if (obj instanceof selectedRows) {
            console.log('UNDALL', obj);
        }else {
            console.log('ILLALLO');
        }
    })
    this.inv_selected = selectedRows.length;

    console.log("selectedRow",selectedRows, selectedRows.length);
}