<script src="js/jquery.js"></script>
<script type="text/javascript">
<!--
$(document).ready(function(){
var len = $("#group span").size();//獲取span標簽的個數
var arr = [];
for(var index = 0; index < len-1; index++){//創建一個數字數組
arr[index] = index;
}
$.each(arr, function(i){//循環得到不同的id的值
var idValue = $("#group span").eq(i).attr("id");
if(idValue != ''){
alert(idValue);
}
});
});
//-->
</script>
<span id="group">
<span id="0_1">aaa,
<span group_id="0_1" class="icon_close"> </span>
</span>
<span id="0_2">bbb,
<span group_id="0_2" class="icon_close"> </span>
</span>
<span id="0_3">ccc,
<span group_id="0_3" class="icon_close"> </span>
</span>
<span id="0_4">ddd,
<span group_id="0_4" class="icon_close"> </span>
</span>
<span id="0_5">eee,
<span group_id="0_5" class="icon_close"> </span>
</span>
</span>

這樣就會得到你想要的所有的id:
0_1
0_2
0_3
0_4
0_5