如何在有角度的材质垫选择中按升序或降序对DropdownData进行排序？

Question

如何按字母顺序排列数组

<mat-form-field">
                <mat-select placeholder="Select Service">
                <mat-option *ngFor="let service of servicecalldropdowns" [value]="service.ServiceCall" 
                  (click)="selected($event,service,service.ServiceCall)">
                  {{service.ServiceCall}}</mat-option>  
              </mat-select>