Convert dd-mm-yyyy string to date

i am trying to convert a string in the format dd-mm-yyyy into a date object in JavaScript using the following:

 var from = $("#datepicker").val();
 var to = $("#datepickertwo").val();
 var f = new Date(from);
 var t = new Date(to);

("#datepicker").val() contains a date in the format dd-mm-yyyy.
When I do the following, I get “Invalid Date”:

alert(f);

Is this because of the ‘-‘ symbol? How can I overcome this?