title: Angular / send another get request on every change on select
body: <p>I have two selects where with one select you choose cars and on another select you get specific models for that car with get request.</p>
  <p><strong>component.html</strong></p>
  <pre><code>  &lt;mat-form-field appearance=&quot;fill&quot;&gt;
      &lt;mat-label&gt;Brand&lt;/mat-label&gt;
      &lt;mat-select multiple formControlName=&quot;Brand&quot; (selectionChange)=&quot;getModels($event)&quot;&gt;
        &lt;mat-option *ngFor=&quot;let item of vehicles&quot; [value]=&quot;item&quot;&gt;{{item}}&lt;/mat-option&gt;
      &lt;/mat-select&gt;
    &lt;/mat-form-field&gt;
  
    &lt;mat-form-field appearance=&quot;fill&quot;&gt;
      &lt;mat-label&gt;მოდელი&lt;/mat-label&gt;
      &lt;mat-select multiple formControlName=&quot;VehicleCategory&quot;&gt;
        &lt;mat-option *ngFor=&quot;let item of inputValue&quot; [value]=&quot;item&quot;&gt;{{item}}&lt;/mat-option&gt;
      &lt;/mat-select&gt;
    &lt;/mat-form-field&gt;
  </code></pre>
  <p>so on every multiple choice it seperates request with commas like this:</p>
  <pre><code>http://localhost:5001/api/Vehicle/Brands/BENTLEY,DACIA,AUDI,HONDA/Models 
  </code></pre>
  <p>here is the code i did for that:</p>
  <p><strong>component.ts</strong></p>
  <pre><code>  getModels(form) {
          // get models
          this.inputValue = this.newCampaignForm.get(&quot;Brand&quot;).value;
          this.campaignService.getModels(this.inputValue).subscribe((data: any[])=&gt;{
            this.inputValue = data;
          });
    }
  </code></pre>
  <p><strong>service.ts</strong></p>
  <pre><code>    public getModels(inputValue: string){
      return this.http.get(this.API_SERVER + '/Vehicle' + '/Brands' + '/' + inputValue + '/Models');
    }
  </code></pre>
  <p>What i want is for every time you select option new api call gets called, not with commas.</p>
  <p>like this for example:</p>
  <pre><code>http://localhost:5001/api/Vehicle/Brands/OPEL/Models
  
  http://localhost:5001/api/Vehicle/Brands/BMW/Models
  </code></pre>