<form id="my_form" method="get" action="">

            <input type="hidden" name="action" value="show" />

            <select onchange="submitForm();" name="kind" style="background:#fff;border:1px solid #ccc;">

                <option value="all"></option>

                <option value="all">默认全部</option>

                <option value="1">文字广告</option>

                <option value="2">头部广告690x80</option>

                <option value="3">侧栏广告270x200</option>

            </select>

    </form>

//select单击提交表单

function submitForm(){

    var form = document.getElementById("my_form");//获取form表单对象

    form.submit();//form表单提交

}