Read value of select box

could somebody please tell me how to achieve the following:

I have a SELECT with different OPTIONs. When I click on one of these opt开发者_如何学JAVAions I want the value to be shown in a DIV. I tried it with this.value but for some reason I am still doing something wrong. Can somebody please help?

Thanks

var select = document.getElementById("mySelectId");
select.options[select.selectedIndex].value;