javawscript 三级菜单的实现原理_javascript技巧

省份： 城市： 区县： 省份,城市，区县数据结构：【名称，父类ID,当前ID】 onChange="changelocation2(document.editForm.smalllocation.options[document.editForm.smalllocation.selectedIndex].value)"根据selectedIndex取得下一级关联菜单的父类ID,复制代码 代码如下:function changelocation(locationid) { document.editForm.smalllocation.length = 0; // document.editForm.dlmc0.length = 0; document.getElementById("dlmc0").length=0; //document.editForm.dlmc0.options[0] = new Option('==请选择==',''); document.getElementById("dlmc0").options[0] = new Option('==请选择==',''); //alert(locationid); var locationid=locationid; var i; document.editForm.smalllocation.options[0] = new Option('==请选择==',''); for (i=0;i { if (subcat[i][1] == locationid) { document.editForm.smalllocation.options[document.editForm.smalllocation.length] = new Option(subcat[i][0], subcat[i][2]); } } }