html slelect 标签默认值

<select name="channelCode" id="channelCode" class="all_input" style="width:165px;margin-left:8px" >
<option value="">全部</option>
<c:forEach var="list" items="${channelList}">
<option value="${list.channelCode}">${list.channelName}</option>
</c:forEach>
</select>

{label: '银行通道名称', name:'channelCode', index:'channelCode', width:120,
formatter:function(cellvalue, options, rowObject) {
return getSelectText('#channelCode', cellvalue);
}
},

function getSelectText(selectObj, value) {
var obj = $(selectObj).find("option[value='" + value + "']");
return obj.text();
}