Validation of select

Question

I have the following HTML

<select class="cadastroDireitaInput cadastroSiteSexo" id="sexo" name="sexo">
  <option value="">Selecione</option>
  <option value="Feminino">Feminino</option>
  <option value="Masculino">Masculino</option>
</select>

I have a JS that checks if the fields are filled in, for example, this line of code:

if($.trim($('#nomeFormUS').val())=='')alert('Informe seu nome!');

In this case, it checks whether an input is filled in.

Now, how do I check if any Options have been selected from that Select?

Answer 1

I use it this way:

<script>
if(nome_formuario.nome_do_select.selectedIndex==0){
            alert("Informe o status do contrato");
            form.st_contrato.focus();
            return false;
        }
</script>

Answer 2

but the correct one would already bring as a standard some sex ... simple problem and unless to worry

  $('#sexo').change(function(){
       var value = $(this).val();
          if(value == ''){
            alert('Escolha um sexo');        
        }
    });

Answer 3

You can use the .val() also or use pure javascript .value

Take a look at this example that makes "false" Lert when choosing the first option and "true" in the others:

$('#sexo').on('change', function(){
    $('#resultado').text(!!this.value);
});

Demo: jsFiddle

So your code could be: (jsFiddle)

 if(!this.value) alert('Informe seu sexo!');