(function($){
//初始化清除按钮 function initClear(target){
var jq = $(target);
var opts = jq.data('combo').options;
var combo = jq.data('combo').combo;
var arrow = combo.find('span.combo-arrow');
var clear = arrow.siblings("span.combo-clear");
if(clear.size()==0){
//创建清除按钮。 clear = $('<span class="combo-clear" style="height: 20px;
"></span>');
//清除按钮添加悬停效果。 clear.unbind("mouseenter.combo mouseleave.combo").bind("mouseenter.combo mouseleave.combo", function(event){
var isEnter = event.type=="mouseenter";
clear[isEnter ? 'addClass' : 'removeClass']("combo-clear-hover");
}
);
//清除按钮添加点击事件，清除当前选中值及隐藏选择面板。 clear.unbind("click.combo").bind("click.combo",function(){
jq.combo("setValue","").combo("setText","");
jq.combo('hidePanel');
}
);
arrow.before(clear);
}
;
var input = combo.find("input.combo-text");
input.outerWidth(input.outerWidth()-clear.outerWidth());
opts.initClear = true;
//已进行清除按钮初始化。 }
//扩展easyui combo添加清除当前值。 var oldResize = $.fn.combo.methods.resize;
$.extend($.fn.combo.methods,{
initClear:function(jq){
return jq.each(function(){
initClear(this);
}
);
}
, resize:function(jq){
//调用默认combo resize方法。 var returnValue = oldResize.apply(this,arguments);
var opts = jq.data("combo").options;
if(opts.initClear){
jq.combo("initClear",jq);
}
return returnValue;
}
}
);
}
(jQuery));

<select id="myselect" panelHeight="auto" style="width: 102px;
" editable="true" name="itcast"> <option value="0">成都</option> <option value="1">传智播客</option> <option value="2">姚欣</option> <option value="3">小星星</option></select>

$('#myselect').combobox({
required : true, editable : false}
).combobox("initClear");

.combo-clear {
background-color: #E0ECFF;
width: 18px;
height: 20px;
overflow: hidden;
display: inline-block;
vertical-align: top;
cursor: pointer;
opacity: 0.6;
filter: alpha(opacity=60);
background: url('images/combo_clear.png') no-repeat center center;
}
.combo-clear-hover {
opacity: 1.0;
filter: alpha(opacity=100);
background-color: #eaf2ff;
}