title: Angular - how to set a default option in a dropdown list
body: <p>I'm trying to implement a dropdown list with ngfor, but I have two issue.</p>
  
  <ol>
  <li><p>I don't get a default value selected on the first element. The array is having 4 element. With the first ngFor at the mat-select I want to select 4 items and the first item preferably being selected per default.</p></li>
  <li><p>There is being shown an unwanted empty arrow (line) at the end.</p></li>
  </ol>
  
  <p>could someone please suggest a better solution. This is my implementations, which I have done after browsing so many post on SO on this topic.</p>
  
  <pre><code>  &lt;mat-select *ngFor="let level of myArray; let i=index " placeholder="{{myArray[i+1].name}}"&gt;
             &lt;mat-option *ngFor="let child of level.children | keyvalue" value="{{child.value.name}}" &gt;
                {{child.value.name}}
             &lt;/mat-option&gt;
              {{level.name}}
    &lt;/mat-select&gt;
  </code></pre>