Visibility With Divs

I was trying to make a script that when you click an image, a div is made hidden or visible. I'm not really sure how to describe it other than that, so here's the code.

<script language="JavaScript">
visibility = visible;
	function menu(whichMenu){
		if (document.getElementById)
{if (document.getElementById(whichMenu).style.visibility == visible){
whatState = hidden;
} 

else {whatState = visible;
}
document.getElementById(whichMenu).style.visibility = whatState;
}
	
	else {

if (document[whichMenu].visibility == visible){
whatState = hidden;
}

 else {whatState = visible;
}
document[whichMenu.visibility = whatState;
}

	}
	</script>

Code (markup):

The image is just simply:

<img onClick="menu('leftcontent1')" ...

Code (markup):

Can someone tell me why this isn't working? Thanks!

 

visible, hidden should be a string and not a variable.
if you want you can set a variable in the global scope that says :

var visible = "visible";
var hidden = "hidden";

Code (markup):

good luck

 

You've seriously overcomplicated this! All you need is a function like:

function toogle(id)
{
var elem = document.getElementById(id);
if(!elem) return;

if(elem.style.visibility == 'hidden') elem.style.visibility = 'visible';
else elem.style.visibility = 'hidden';
}

<img onClick=toggle('leftcontent1') ...