number validation in typescript
<input type="text" pattern="\d*" maxlength="10" onkeydown="javascript: return event.keyCode === 9 || event.keyCode === 8 || event.keyCode === 46 ? true : !isNaN(Number(event.key))" class="form-control form-control-solid form-control-lg"
[ngModelOptions]="{standalone: true}" [disabled]="!onOff"
[(ngModel)]="communityModel.associationContactNo" />