Show/Hide DIV

What are you trying to accomplish? An easy way could be to have:

if(!document.getElementById && document.all) {
   document.getElementById = function(id) {return document.all[id];}
} elseif(!document.getElementById && document.layers) {
   document.getElementById = function(id) {return document.layers[id];}
} else {
   document.getElementById = function(id) {return null;}
}

Then you should be able to use document.getElementById in the most browsers, although you could create more artifial functions offcourse.

-r-

I've replaced all the code now with just:
function sd(layerName) {
      document.getElementById(layerName).style.display = 'block';
      hd(layerName+"link");
}

function hd(layerName) {
      document.getElementById(layerName).style.display = 'none';
}

And it works fine. Thanks.

Make sure you test all your browsers.

-r-

Is this something you like ?

I debugged your code, and tested with IE, FF


<script language="javascript">
var what = null;
var newbrowser = true;
var check = false;
function init() {
     if (document.layers) {
          layerRef="document.layers";
          styleSwitch="";
          visibleVar="show";
          screenSize = window.innerWidth;
          what ="ns4";
     }
     else if (document.all) {
          layerRef="document.all";
          styleSwitch=".style";
          visibleVar="visible";
          screenSize = document.body.clientWidth + 18;
          what ="ie4";
     }
     else if (document.getElementById) {
          layerRef="document.getElementByID";
          styleSwitch=".style";
          visibleVar="visible";
          what="dom1";
     }
     else {
          what="none";
          newbrowser = false;
     }
     check = true;
}

function sd(layerName) {
     if (check) {
          if (what == "none") {
               return;
          }
          else if (what == "dom1") {
               document.getElementById(layerName).style.height="";
               document.getElementById(layerName).style.visibility="visible";
          }
          else {
               eval(layerRef+'["'+layerName+'"]'+styleSwitch+'.height=""');
               eval(layerRef+'["'+layerName+'"]'+styleSwitch+'.visibility="visible"');
          }
          hd(layerName+"link");
     }
     else {
          return;
     }
}

function hd(layerName) {
    if (check) {
          if (what == "none") {
               return;
          }
          else if (what == "dom1") {
               document.getElementById(layerName).style.visibility="hidden";
          }
          else {
               eval(layerRef+'["'+layerName+'"]'+styleSwitch+'.visibility="hidden"');
          }
     }
     else {
          return;
     }
}
</script>
<input type="button" value="Show myId" onClick="init(); sd('myId');">
<input type="button" value="Hide myId" onClick="init(); hd('myId');">
<div id="myId" style="visibility:visible; height:100px;">ID = myId
</div>
<div id="myIdlink" style="visibility:visible; height:100px;">ID = myIdlink
</div>