PHP bulk form post using ajax

I have a form with 100 fields ,how do i post the data to a php u开发者_StackOverflowsing ajax with out refreshing the page,also i do not want to concatenate the field values without getelementbyid in the xmlhttprequest.

Thanks

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in jQuery could be something like

$.post("/path", $("#form-id").serialize(), function(ev){
  alert("done!");
});