[jquery] Get selected key/value of a combo box using jQuery

Please, how can I get the selected key and value of a HTML select combo box using jQuery?

$(this).find("select").each(function () {
    if ($.trim($(this).val()) != '') {
        searchString += $.trim($(this).val()) + " "; //This gives me the key. How can I get the value also?
    }
});

Thanks

$("#elementName option").text(); 

This will give selected text of Combo-Box.

$("#elementName option").val();

This will give selected value associated selected item in Combo-Box.

$("#elementName option").length;

It will give the multi-select combobox values in the array and length will give number of element of the array.

Note:#elementName is id the Combo-box.

$(this).find("select").each(function () {
    $(this).find('option:selected').text();
});

This works:

<select name="foo" id="foo">
<option value="1">a</option>
<option value="2">b</option>
<option value="3">c</option>
</select>
<input type="button" id="button" value="Button" />

$('#button').click(function() {
    alert($('#foo option:selected').text());
    alert($('#foo option:selected').val());
});

<select name="foo" id="foo">
 <option value="1">a</option>
 <option value="2">b</option>
 <option value="3">c</option>
  </select>
  <input type="button" id="button" value="Button" />
  });
  <script> ("#foo").val() </script>

which returns 1 if you have selected a and so on..