Default option of select is not showing

Issue

I have one select that i need to put a default select option, but it's not showing in my template.

I tried:

<div class="select">

    <select (change)="calculaMes(mesEscolhido)" [(ngModel)]="mesEscolhido" name="selectMesEscolhido"
    class="select-text">
       <option class="dropdown-item" disabled selected value>Teste</option>
       <option [hidden]="datasComMovimentacoes[x].data == mesEscolhido" *ngFor="let mes of datasComMovimentacoes;let x = index"
       class="dropdown-item">{{mes.data}}</option>
    </select>

   <span class="select-highlight"></span>
   <span class="select-bar"></span>

</div>

I don't believe this is caused by my css, but, this is my css:

 .select {
    font-family:
      'Roboto','Helvetica','Arial',sans-serif;
      position: relative;
      width: 100%;
      margin-top: 5%;
      font-size: 18px;
      color: #757575!important;
  }

  .select-text {
      margin-top: 10%;
      position: relative;
      font-family: inherit;
      background-color: transparent;
      color: #757575!important;
      width: 100%;
      font-size: 18px;
      border-radius: 0;
      border: none;
      border-bottom: 1px solid rgba(0,0,0, 0.12);
  }

  /* Remove focus */
  .select-text:focus {
      outline: none;
      color: #757575!important;
      border-bottom: 1px solid rgba(0,0,0, 0);
  }

      /* Use custom arrow */
  .select .select-text {
      appearance: none;
      color: #757575!important;
      -webkit-appearance:none
  }

This is my result in template:

Solution

The default option will be selected if the value attribute of the option tag is set to the default value of the selectedOption property on your Component. Let's say you didn't initialize the selectedOption property, then by default it's value will be undefined. And so, this value attribute of the option tag should be undefined in that case.

...
<option class="dropdown-item" disabled selected value="undefined">Select an Option</option>
...

Here's a Sample StackBlitz for your ref.

Answered By - SiddAjmera