i have two mat-select and want to filter second mat-select by selected value in first mat-select: html code is :
<mat-label>products</mat-label>
<mat-form-field appearance="fill" class = "tp-full-width">
<mat-select #captionlist>
<mat-option *ngFor="let p of list_product.data" [value]="p">
{{ p.description }}
</mat-option>
</mat-select>
</mat-form-field>
<mat-form-field appearance="fill" class = "tp-full-width">
<mat-label>brand</mat-label>
<mat-select #brandlist>
<mat-option *ngFor="let m of list_brands.data" [value]="m">
{{ m.BDesc }}
</mat-option>
</mat-select>
</mat-form-field>
pls,help me ,what write in type script to do this?