title: Can I have the previous ajax calling stopped when I raise a new one?
body: <p>I'm using jQuery's <code>autocomplete</code>, but have found a performance-related issue - if I input 'abc', it will be scanning by 'a', by 'ab', and by 'abc', at a once, how can I stop the previous 'a', 'ab' when ajax calling is doing searching by 'abc'?</p>
  
  <p>The similar case is:
  I use jQuery DataTables, and want to do some searching like, I typed something to search (call search web method), and clicked button - 'Search' 3 times at a once, or changed search text just when I clicked 'Search', and raise a new search, how can I stop the previous useless ajax calling?</p>