jquery - javascript return statement not working -

i have bug code won't exit routine. i'm using return statement... doesn't seem working.
have following code inside click event:

    $.getjson(                  url = 'myserver/controller/checkforduplicate',           parameters,           function(data)  {                         if (data=='true') {                             alert(data);                             $('#verror').html("a duplicate entry exists");                                   return false;                         }                 }             );           console.log($('#myform').serialize() ); 

when input data should considered duplicate , trigger click event, system doesn't exit still gets console.log statement.

edit 1

i've reviewed answers found at: how return response asynchronous call? i'm reading, haven't defined callback function? thought that's doing "function(data) {}" code... in addition stackoverflow, i've been using:

http://www.tutorialspoint.com/jquery/ajax-jquery-getjson.htm

it seems in above example, referring function(jd) callback. according above article, syntax is:

$.getjson( url, [data], [callback] )

perhaps i'm still missing something... patience.

you cannot return asynchronous function.

you need use callback.