JS FirstChild, NextSibling, LastChild, previoussibling, parentnode

NextSibling Next Sibling node

PreviousSibling Last Brother

ParentNode Father Node

1<select><option value= "Zs" > Zhongshan </option><option value= "GZ" > Guangzhou </option><option Value= "zh" > Shenzhen </option><option value= "zh" > Zhuhai </option></select>2<script type= "Text/javascript" >3               //gets the number of child elements under the <select> element node4               //var selectelement = document.getElementsByTagName ("select") [0];5               //var size = selectElement.childNodes.length;6               //alert ("+size+" is a common element in "select");7               8               //get the "Zhongshan" string9               //var selectelement = document.getElementsByTagName ("select") [0];Ten               //var zselement = selectelement.firstchild; One               //var zs = zselement.innerhtml; A               //alert (ZS); -                -               //get the "Guangzhou" string the               //var selectelement = document.getElementsByTagName ("select") [0]; -               //var zselement = selectelement.firstchild; -               //var gzelement = zselement.nextsibling; -               //var gz = gzelement.innerhtml; +               //alert (GZ); -                +               //get the "Zhuhai" string A               //var selectelement = document.getElementsByTagName ("select") [0]; at               //var zhelement = selectelement.lastchild; -               //var zh = zhelement.innerhtml; -               //alert (zh); -                -               //get the "Shenzhen" string -               //var selectelement = document.getElementsByTagName ("select") [0]; in               //var zhelement = selectelement.lastchild; -               //var szelement = zhelement.previoussibling; to               //var sz = szelement.innerhtml; +               //alert (SZ); -                the               //Delete "Guangzhou" element *               varGzelement = document.getelementsbytagname ("option") [1]; $               varSelectElement =Gzelement.parentnode;Panax Notoginseng Selectelement.removechild (gzelement); -                the                +                A                the</script>