<mat-form-field>
        <input type="text" placeholder="Select company" matInput [formControl]="myControl" [matAutocomplete]="auto">
      </mat-form-field>

      <mat-autocomplete #auto="matAutocomplete">
        <mat-option *ngFor="let option of testCompanies" [value]="option">
          {{ option }}
        </mat-option>
      </mat-autocomplete>

export class EditModalContent /* implements OnInit */ {
testCompanies: string[] = ["One", "Two", "Three", "Four"];
myControl = new FormControl();
filteredOptions: Observable<string[]>;

constructor(public activeModal: NgbActiveModal) {}