I need a html \'control\' similar to \"CheckedListBox\" from WinForms:
I don't believe you can do that with a standard select box, but if you make it into a custom select box and then add in your input
checkboxes to the items, you could probably achieve what you desire. Do some searches for a jquery custom select box to find what suits you. Here a just a couple I found (untested, and thus not necessarily recommending...)
http://www.mypocket-technologies.com/jquery/SelectBoxPlugin/
http://dervish.wsisiz.edu.pl/~suszynsk/jQuery/demos/jquery-selectbox/