js相关属性的使用

//前后dom节点

function   checkPre(id)   {
var   o   =   document.getElementById(id);
var   oPre   =   o.previousSibling;
var   oNext   =   o.nextSibling;
var   oParent   =   o.parentNode;
var   oChild   =   o.children[0];
alert( "Current:/n "   +   o.innerHTML);
alert( "Previous:/n "   +   oPre.innerHTML);
alert( "Next:/n "   +   oNext.innerHTML);
alert( "Parent:/n "   +   oParent.innerHTML);
alert( "Child:/n "   +   oChild.innerHTML);
}