Show Drop Down Menu

[sandeep_1987]

I want to show a menu.As u see in websites,wen we move a mouse over the menu item,Drop down menu appears.How to do that?

See in Pic on URL
http://www.vbforums.com/newthread.php?do=newthread&f=31

[shenulal]

Hai,
You might be talking about javascript menu right?

You can create these menus in two ways.

1. In asp.net we have control called Menu Control. Using that you can easily obtain this requirement

2. You have to use Javascript for creating the menu. Usually in most site we will have javascript menus as its load faster than the asp.net menu.

I will give you an example:

var disappeardelay=250  //menu disappear speed onMouseout (in miliseconds)
var enableanchorlink=0 //Enable or disable the anchor link when clicked on? (1=e, 0=d)
var hidemenu_onclick=1 //hide menu when user clicks within menu? (1=yes, 0=no)

var ie5=document.all
var ns6=document.getElementById&&!document.all

function getposOffset(what, offsettype){
var totaloffset=(offsettype=="left")? what.offsetLeft : what.offsetTop;
var parentEl=what.offsetParent;
while (parentEl!=null){
totaloffset=(offsettype=="left")? totaloffset+parentEl.offsetLeft : totaloffset+parentEl.offsetTop;
parentEl=parentEl.offsetParent;
}
return totaloffset;
}

function showhide(obj, e, visible, hidden){
if (ie5||ns6)
dropmenuobj.style.left=dropmenuobj.style.top=-500
if (e.type=="click" && obj.visibility==hidden || e.type=="mouseover")
obj.visibility=visible
else if (e.type=="click")
obj.visibility=hidden
}

function iecompattest(){
return (document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body
}

function clearbrowseredge(obj, whichedge){
var edgeoffset=0
if (whichedge=="rightedge"){
var windowedge=ie5 && !window.opera? iecompattest().scrollLeft+iecompattest().clientWidth-15 : window.pageXOffset+window.innerWidth-15
dropmenuobj.contentmeasure=dropmenuobj.offsetWidth
if (windowedge-dropmenuobj.x < dropmenuobj.contentmeasure)
edgeoffset=dropmenuobj.contentmeasure-obj.offsetWidth
}
else{
var topedge=ie5 && !window.opera? iecompattest().scrollTop : window.pageYOffset
var windowedge=ie5 && !window.opera? iecompattest().scrollTop+iecompattest().clientHeight-15 : window.pageYOffset+window.innerHeight-18
dropmenuobj.contentmeasure=dropmenuobj.offsetHeight
if (windowedge-dropmenuobj.y < dropmenuobj.contentmeasure){ //move up?
edgeoffset=dropmenuobj.contentmeasure+obj.offsetHeight
if ((dropmenuobj.y-topedge)<dropmenuobj.contentmeasure) //up no good either?
edgeoffset=dropmenuobj.y+obj.offsetHeight-topedge
}
}
return edgeoffset
}

function dropdownmenu(obj, e, dropmenuID){
if (window.event) event.cancelBubble=true
else if (e.stopPropagation) e.stopPropagation()
if (typeof dropmenuobj!="undefined") //hide previous menu
dropmenuobj.style.visibility="hidden"
clearhidemenu()
if (ie5||ns6){
obj.onmouseout=delayhidemenu
dropmenuobj=document.getElementById(dropmenuID)
if (hidemenu_onclick) dropmenuobj.onclick=function(){dropmenuobj.style.visibility='hidden'}
dropmenuobj.onmouseover=clearhidemenu
dropmenuobj.onmouseout=ie5? function(){ dynamichide(event)} : function(event){ dynamichide(event)}
showhide(dropmenuobj.style, e, "visible", "hidden")
dropmenuobj.x=getposOffset(obj, "left")
dropmenuobj.y=getposOffset(obj, "top")
dropmenuobj.style.left=dropmenuobj.x-clearbrowseredge(obj, "rightedge")+"px"
dropmenuobj.style.top=dropmenuobj.y-clearbrowseredge(obj, "bottomedge")+obj.offsetHeight+"px"
}
return clickreturnvalue()
}

function clickreturnvalue(){
if ((ie5||ns6) && !enableanchorlink) return false
else return true
}

function contains_ns6(a, b) {
while (b.parentNode)
if ((b = b.parentNode) == a)
return true;
return false;
}

function dynamichide(e){
if (ie5&&!dropmenuobj.contains(e.toElement))
delayhidemenu()
else if (ns6&&e.currentTarget!= e.relatedTarget&& !contains_ns6(e.currentTarget, e.relatedTarget))
delayhidemenu()
}

function delayhidemenu(){
delayhide=setTimeout("dropmenuobj.style.visibility='hidden'",disappeardelay)
}

function clearhidemenu(){
if (typeof delayhide!="undefined")
clearTimeout(delayhide)
}

You copy the above code and create a js file. Like (link.js)

then call this script in the html page like <script type="text/javascript" src="*put the path to link.js*"/> in the html add code for the menu items

<table>
<tr>       
<td><a  href="c#.html" onMouseover="dropdownmenu(this, event, 'anylinkCSharp')">C#</a></td> </tr></table>

<div id="anylinkCSharp">
<a href="csharp.html">C#</a> 
<a href="aspnet.html">asp.net</a>
<a href="sqlserver.html">sqlserver</a>
</div>

I think this will work for you. Update me with the result.

Thanks,
Shenu