本文實例講述了JavaScript實現鼠標點擊後層展開效果的方法。分享給大家供大家參考。具體分析如下：
這段JavaScript代碼可實現鼠標點擊後層展開的功能，代碼稍嫌復雜，重在學習研究，有興趣的可以修改簡化一下。
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>層展開折疊</title> </head> <body> <style type="text/css"> DIV.clTopMenu{ position:absolute; width:101; height:150; clip:rect(0,101,14,0); visibility:hidden; z-index:31; layer-background-color:#EEEEEE; background-color:#00CCFF } DIV.clTopMenuBottom{ position:absolute; width:101; height:3; clip:rect(0,101,3,0); top:11; layer-background-color:#CECFCE; background-color:#000099; z-index:2 } DIV.clTopMenuText{ position:absolute; width:91; left:5; top:15; font-family:"Arial", "Helvetica", "sans-serif"; font-size:9pt; background-color:#EEEEEE; z-index:1; color: #000000 } a:link { color: #000000; text-decoration: none } </style> <script language="JavaScript" type="text/javascript"> function lib_bwcheck(){ //Browsercheck (needed) this.ver=navigator.appVersion this.agent=navigator.userAgent this.dom=document.getElementById?1:0 this.opera5=this.agent.indexOf("Opera 5")>-1 this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom && !this.opera5)?1:0; this.ie6=(this.ver.indexOf("MSIE 6")>-1 && this.dom && !this.opera5)?1:0; this.ie4=(document.all && !this.dom && !this.opera5)?1:0; this.ie=this.ie4||this.ie5||this.ie6 this.mac=this.agent.indexOf("Mac")>-1 this.ns6=(this.dom && parseInt(this.ver) >= 5) ?1:0; this.ns4=(document.layers && !this.dom)?1:0; this.bw=(this.ie6 || this.ie5 || this.ie4 || this.ns4 || this.ns6 || this.opera5) return this } var bw=new lib_bwcheck() nPlace=0 var nNumberOfMenus=2 var nMwidth=101 var nPxbetween=20 var nFromleft=10 var nFromtop=20 var nBgcolor='#CECFCE' var nBgcolorchangeto='#6380BC' var nImageheight=11 function makeNewsMenu(obj,nest){ nest=(!nest) ? "":'document.'+nest+'.' this.css=bw.dom? document.getElementById(obj).style:bw.ie4?document.all[obj].style:bw.ns4?eval(nest+"document.layers." +obj):0; this.evnt=bw.dom? document.getElementById(obj):bw.ie4?document.all[obj]:bw.ns4?eval(nest+"document.layers." +obj):0; this.scrollHeight=bw.ns4?this.css.document.height:this.evnt.offsetHeight this.moveIt=b_moveIt;this.bgChange=b_bgChange; this.slideUp=b_slideUp; this.slideDown=b_slideDown; this.clipTo=b_clipTo; this.obj = obj + "Object"; eval(this.obj + "=this") } function b_moveIt(x,y){this.x=x; this.y=y; this.css.left=this.x; this.css.top=this.y} function b_bgChange(color){if(bw.dom || bw.ie4) this.css.backgroundColor=color; else this.css.bgColor=color} function b_clipTo(t,r,b,l){ if(bw.ns4){this.css.clip.top=t; this.css.clip.right=r; this.css.clip.bottom=b; this.css.clip.left=l }else this.css.clip="rect("+t+","+r+","+b+","+l+")"; } function b_slideUp(ystop,moveby,speed,fn,wh){ if(!this.slideactive){ if(this.y>ystop){ this.moveIt(this.x,this.y-5); eval(wh) setTimeout(this.obj+".slideUp("+ystop+","+moveby+","+speed+",'"+fn+"','"+wh+"')",speed) }else{ this.slideactive=false; this.moveIt(0,ystop); eval(fn) } } } function b_slideDown(ystop,moveby,speed,fn,wh){ if(!this.slideactive){ if(this.y<ystop){ this.moveIt(this.x,this.y+5); eval(wh) setTimeout(this.obj+".slideDown("+ystop+","+moveby+","+speed+",'"+fn+"','"+wh+"')",speed) }else{ this.slideactive=false; this.moveIt(0,ystop); eval(fn) } } } function newsMenuInit(){ oTopMenu=new Array() zindex=10 for(i=0;i<=nNumberOfMenus;i++){ oTopMenu[i]=new Array() oTopMenu[i][0]=new makeNewsMenu('divTopMenu'+i) oTopMenu[i][1]=new makeNewsMenu('divTopMenuBottom'+i,'divTopMenu'+i) oTopMenu[i][2]=new makeNewsMenu('divTopMenuText'+i,'divTopMenu'+i) oTopMenu[i][1].moveIt(0,nImageheight) oTopMenu[i][0].clipTo(0,nMwidth,nImageheight+3,0) if(!nPlace) oTopMenu[i][0].moveIt(i*nMwidth+nFromleft+(i*nPxbetween),nFromtop) else{ oTopMenu[i][0].moveIt(nFromleft,i*nImageheight+nFromtop+(i*nPxbetween)) oTopMenu[i][0].css.zIndex=zindex-- } oTopMenu[i][0].css.visibility="visible" } } function topMenu(num){ if(oTopMenu[num][1].y==nImageheight) oTopMenu[num][1].slideDown(oTopMenu[num][2].scrollHeight+20,10,40,'oTopMenu['+num+'][0].clipTo(0,nMwidth,oTopMenu['+num+'][1].y+3,0)','oTopMenu['+num+'][0].clipTo(0,nMwidth,oTopMenu['+num+'][1].y+3,0)') else if(oTopMenu[num][1].y==oTopMenu[num][2].scrollHeight+20) oTopMenu[num][1].slideUp(nImageheight,10,40,'oTopMenu['+num+'][0].clipTo(0,nMwidth,oTopMenu['+num+'][1].y+3,0)','oTopMenu['+num+'][0].clipTo(0,nMwidth,oTopMenu['+num+'][1].y+3,0)') } function menuOver(num){oTopMenu[num][1].bgChange(nBgcolorchangeto)} function menuOut(num){oTopMenu[num][1].bgChange(nBgcolor)} onload=newsMenuInit; </script> <div id="divTopMenu0" class="clTopMenu" align="center" style="height: 170; left: 20; top: 20"><span class="css3"><a href="#" onMouseOver="menuOver(0)" onMouseOut="menuOut(0)" onClick="topMenu(0); if(bw.dom || bw.ie4)this.blur(); return false">點擊展開</a> </span> <div id="divTopMenuText0" class="clTopMenuText"> <span class="css3"> 鼠標點擊後層展開JavaScript鼠標點擊後層展開JavaScript。 </span> </div> <div id="divTopMenuBottom0" class="clTopMenuBottom" style="top: 11; height: 10"></div> </div> </div> </body> </html>希望本文所述對大家的javascript程序設計有所幫助。