JQuery在循环中绑定事件的问题详解

<input type="text" name="username" id="username_1" value="" /><input type="text" name="username" id="username_2" value="" /><input type="text" name="username" id="username_3" value="" />

$(function(){ for(var i=1; i<=3; i++){  $('#username_'+i).onclick(function(){   alert(i);  }); }});

$(function(){ for (var i=1; i<=3; i++){  $("#username_"+i).bind("click", {index: i}, clickHandler); } function clickHandler(event) {  var i= event.data.index;  alert(i); }});