jquery提交form表单时禁止重复提交的方法

$(document).ready(function(){
 $("form").submit(function(){
   if(typeofjQuery.data(this,"disabledOnSubmit")=="undefined"){
     jQuery.data(this,"disabledOnSubmit",{submited:true});
     $("input[type=submit],input[type=button]",this).each(function(){
       $(this).attr("disabled","disabled");
     });
     returntrue;
   }
   else
   {
     returnfalse;
   }
 });
});