本文实例讲述了JS+CSS简单树形菜单实现方法。分享给大家供大家参考。具体如下：
这是一款不错的CSS树形菜单，树状列表，当然不全是CSS实现，部分功能还使用了JavaScript代码进行配合，删减了修饰用的菜单图片，大家用的时候自己图片加进去，IMG标签大部分都预留了出来，稍懂Html语法的朋友很容易就看懂的。
运行效果截图如下：
在线演示地址如下：
http://demo.jb51.net/js/2015/js-css-simple-tree-menu-style-codes/
具体代码如下：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>树状列表</title> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" /> <style> *{margin:0px;padding:0px;} A:link{color: #000000; TEXT-DECORATION: none;} A:visited {COLOR: #000000; TEXT-DECORATION: none} A:active {COLOR: #3333ff; TEXT-DECORATION: none} A:hover {COLOR: #ff0000; TEXT-DECORATION: none} .panel{ BACKGROUND: #DDE4EA; COLOR:#654125;} ul { list-style: none; margin: 0; padding: 0; } img{ border:0px; width:16px; height:16px; } #menu{ margin-top: 0px; } .U1 { background: #FFFFFF; border-bottom:1px #9D9D9D solid; } .L1 a:link, .L1 a:visited{ color: #476074; background: url(""); font-size:9pt; display: block; text-decoration: none; height: 24px; } .L1 a:link span, .L1 a:visited span{ background: url("") no-repeat left; padding-left: 15px; height:24px; vertical-align:middle; padding:7px 0px 0px 16px; cursor:pointer; width:100%; } .L1 a:hover{ color: #000000; font-weight:bold; background: url(""); background-position: 0 -24px; } /* 一级菜单 active 效果 */ .L1 a:link.active, .L1 a:hover.active, .L1 a:active.active, .L1 a:visited.active{ background: url(""); background-position: 0 -24px; } .L1 a:link.active span, .L1 a:hover.active span, .L1 a:active.active span, .L1 a:visited.active span{ color: #000000; font-weight:bold; background: url("") no-repeat left; } .L21 a:link, .L21 a:visited, .L22 a:link, .L22 a:visited, .L3 a:link, .L3 a:visited{ color: #444659; background: none; height: 24px; font-size:9pt; display: block; text-decoration: none; padding-left: 13px; background: none; } .L21 a:link span, .L21 a:visited span, .L22 a:link span, .L22 a:visited span, .L3 a:link span, .L3 a:visited span{ vertical-align:middle; padding:7px 0px 0px 16px; background: url("") no-repeat left center; cursor:pointer; width:100%; } .L22 a:link span, .L22 a:visited span, .L3 a:link span, .L3 a:visited span{ background:none; } .L21 a:hover, .L22 a:hover, .L3 a:hover{ background: url("") no-repeat top left; font-weight:bold; } .L3 a:link span, .L3 a:visited span{ padding:7px 0px 0px 26px; } .L4 a:link span, .L4 a:visited span{ padding:7px 0px 0px 36px; } /* 二级菜单 active 效果 */ .L21 a:link.active, .L21 a:hover.active, .L21 a:active.active, .L21 a:visited.active{ background: none; } .L21 a:link.active span, .L21 a:hover.active span, .L21 a:active.active span, .L21 a:visited.active span{ color: #000000; font-weight:bold; background: url("") no-repeat left center; } /* 二、三级菜单 active */ .L22 a:link.active, .L22 a:hover.active, .L22 a:active.active, .L22 a:visited.active, .L3 a:link.active, .L3 a:hover.active, .L3 a:active.active, .L3 a:visited.active{ background: url("") no-repeat left; background-position: 0 -24px; } .L22 a:link.active span, .L22 a:hover.active span, .L22 a:active.active span, .L22 a:visited.active span, .L3 a:link.active span, .L3 a:hover.active span, .L3 a:active.active span, .L3 a:visited.active span{ color: #FFFFFF; font-weight:bold; background: none; } .Ls{ text-align:right; padding-top:4px; height:20px; font-size:9pt; } .setting:link, .setting:visited{ text-decoration: underline; display:block; } </style> </head> <body onLoad="init();"> <div id="sub_tabs"></div> <div id="body"> <> <ul id="menu"> <> <li><a href="javascript:c('m01');" id="m01"><span><img src="" align="absMiddle"/> 路政报表</span></a></li> <ul id="m01d"> <li><a href="javascript:c('f40');" id="f40"><span><img src="" align="absMiddle"/> 路政报表1</span></a></li> <ul id="f40d"> <li><a href="javascript:c('f42');"><span><img src= align="absMiddle"/> 报表内容</span></a></li> <ul id="f42d"><li ><a href="#"><span><img src= align="absMiddle"/>子报表内容</span></a></li></ul> <li><a href="#"><span><img src="" align="absMiddle"/> 报表内容</span></a></li> </ul> <li><a href="javascript:c('f41');" id="f41"><span><img src="" align="absMiddle"/> 路政报表2</span></a></li> <ul id="f41d"> <li><a href="#"><span><img src="" align="absMiddle"/>报表内容</span></a></li> <li><a href="#"><span><img src="" align="absMiddle"/>报表内容</span></a></li> </ul> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> </ul> <> <> <li><a href="javascript:c('m03');" id="m03"><span><img src="" align="absMiddle"/> 路政报表</span></a></li> <ul id="m03d"> <li><a href="javascript:c('f42');" id="f42"><span><img src= align="absMiddle"/> 路政报表1</span></a></li> <ul id="f42d"> <li><a href="#"><span><img src="" align="absMiddle"/> 报表内容</span></a></li> <li><a href="#"><span><img src="" align="absMiddle"/> 报表内容</span></a></li> </ul> <li><a href="javascript:c('f43');" id="f43"><span><img src= align="absMiddle"/> 路政报表2</span></a></li> <ul id="f43d"> <li><a href="#"><span><img src= align="absMiddle"/>报表内容</span></a></li> <li><a href="#"><span><img src= align="absMiddle"/>报表内容</span></a></li> </ul> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> <li><a href="#"><span><img src="" /> 报表内容</span></a></li> </ul> <> </ul> </ul> </div> <script language="JavaScript"> window.onresize=function() { if(!parent.$('frame1')) return; var rows = parent.$('frame1').rows.split(","); if(rows.length < 2 || rows[1]!="*") return; $("bottom_center").style.width = "0px"; if(document.body.clientHeight > $("sub_tabs").clientHeight+$("bottom").clientHeight) $("body").style.height=(document.body.clientHeight-$("sub_tabs").clientHeight-$("bottom").clientHeight)+"px"; var widthTotal = parseInt($("bottom").clientWidth); var widthLeft = parseInt($("bottom_left").clientWidth); var widthRight = parseInt($("bottom_right").clientWidth); if(!isNaN(widthTotal) && !isNaN(widthLeft) && !isNaN(widthRight)) { $("bottom_center").style.width = widthTotal - widthLeft - widthRight + "px"; } }; function init() { window.onresize(); } var sub_menu="1"; function view_menu(id) { set_current(""); if($("menu").innerHTML.toLowerCase().indexOf("<li") >= 0) $("menu_code_"+sub_menu).innerText=$("menu").innerHTML; if($("menu_code_"+id).innerText=="" || isUndefined($("menu_code_"+id).innerText)) { $("menu").innerHTML="<img src='http://www.jb51.netimages/loading.gif' align='absMiddle'> 加载中，请稍候……"; if(id==2) args="MENU_TYPE=SHORTCUT&OA_SUB_WINDOW=0&MENU_DISPLAY="; else if(id==3) args="MENU_TYPE=OA&OA_SUB_WINDOW=0"; else if(id==4) args="MENU_TYPE=FAV&OA_SUB_WINDOW=0"; else if(id==5) args="MENU_TYPE=FIS&OA_SUB_WINDOW=0"; else args="OA_SUB_WINDOW=0"; _get("menu_code.php", args, update_menu, true); } else { $("menu").innerHTML=$("menu_code_"+id).innerText; } if($('link_'+sub_menu)) $('link_'+sub_menu).className=""; $('link_'+id).className="active"; sub_menu=id; setCookie("MENU_UI_1", id); if(id == 5) { openURL("http://www.jb51.net/"); } } function update_menu(req) { if(req.status == 200) { if(req.responseText=="") $("menu").innerHTML="<div>无可访问菜单</div>"; else { $("menu").innerHTML=req.responseText; if(sub_menu == 2) c('mMENU_SHORTCUT'); } } else { $("menu").innerHTML="<div>错误："+req.status+"</div>"; } } var cur_id="",cur_expand=""; var flag=0,sflag=0; //-------- 菜单点击事件 ------- function c(id) { var targetid,targetelement; var strbuf; var el=$(id); if(!el) return; //-------- 如果点击了展开或收缩按钮--------- targetid=el.id+"d"; targetelement=$(targetid); var expandUL=$(cur_expand+"d"); var expandLink=$(cur_expand); if (targetelement.style.display=="none") { if(expandUL && expandLink && el.id.substr(0,1)=="m") { expandLink.className=""; expandUL.style.display='none'; } if(el.id.substr(0,1)=="m") cur_expand=el.id; el.className="active"; targetelement.style.display=''; menu_flag=0; //$("expand_link").src="images/green_minus.gif"; } else { el.className=""; targetelement.style.display="none"; menu_flag=1; //$("expand_link").src="images/green_plus.gif"; var links=document.getElementsByTagName("A"); for (i=0; i<links.length; i++) { el=links[i]; if(el.parentNode.className.toUpperCase()=="L1" && el.className=="active" && el.id.substr(0,1)=="m") { menu_flag=0; // $("expand_link").src="images/green_minus.gif"; break; } } } } //-------- 打开网址 ------- var $ = function(id) {return document.getElementById(id);}; var userAgent = navigator.userAgent.toLowerCase(); var is_opera = userAgent.indexOf('opera') != -1 && opera.version(); var is_ie = (userAgent.indexOf('msie') != -1 && !is_opera) && userAgent.substr(userAgent.indexOf('msie') + 5, 3); function MouseOverBtn(){event.srcElement.className+="Hover";} function MouseOutBtn() {event.srcElement.className=event.srcElement.className.substr(0,event.srcElement.className.indexOf("Hover"));} function CorrectButton() { var inputs=document.getElementsByTagName("INPUT"); for(var i=0; i<inputs.length; i++) { var el = inputs[i]; var elType = el.type.toLowerCase(); var elClass = el.className.toLowerCase(); var elLength = Math.ceil(el.value.replace(/[^x00-xff]/g,"**").length/2); if(elType!="button" && elType!="submit" && elType!="reset" || elClass!="bigbutton"&&elClass!="smallbutton") continue; if(elLength<=3) el.className+="A"; else if(elLength==4) el.className+="B"; else if(elLength>=5 && elLength<=7) el.className+="C"; else if(elLength>=8 && elLength<=11) el.className+="D"; else el.className+="E"; if(is_ie) { el.attachEvent("onmouseover", MouseOverBtn); el.attachEvent("onmouseout", MouseOutBtn); } } } if(is_ie) window.attachEvent("onload", CorrectButton); else window.addEventListener("load", CorrectButton,false); </script> </body> </html>
希望本文所述对大家的JavaScript程序设计有所帮助。