var subval2 = new Array();
//数组结构：一级根值,二级根值,二级显示值

subval2[0] = new Array('12','18','南翠微店')

subval2[1] = new Array('12','19','南西单店')


function changeselect1(locationid)
{
    document.myform.Ushop.length = 0;
    document.myform.Ushop.options[0] = new Option('请选择店名','0');
    for (i=0; i<subval2.length; i++)
    {
        if (subval2[i][0] == locationid)
        {document.myform.Ushop.options[document.myform.Ushop.length] = new Option(subval2[i][2],subval2[i][1]);}
    }
}