Each function in jquery state

You have a selection error in select.#ch

, so it must be select > option:selected

either:

$("option:selected", this).each(function() {
    str += $(this).text() + " ";
});

      

        
        
        
      

    

However, I would rewrite the code like this:

$("select").change(function () {
    var str = $("option:selected", this).map(function() {
        return this.innerHTML;
    }).get().join(" ");

    $("div").text(str);
}).change();

      

        
        
        
      

    

DEMO: http://jsfiddle.net/MpjjE/