Here is the type of JavaScript that you will want to use:
function Is() {
var agent = navigator.userAgent.toLowerCase();
this.major = parseInt(navigator.appVersion);
this.minor = parseFloat(navigator.appVersion);
this.ns = ((agent.indexOf('mozilla')!=-1) &&
((agent.indexOf('spoofer')==-1) && (agent.indexOf('compatible') == -1)));
this.ns2 = (this.ns && (this.major == 2));
this.ns3 = (this.ns && (this.major == 3));
this.ns4b = (this.ns && (this.minor < 4.04));
this.ns4 = (this.ns && (this.major >= 4));
this.ie = (agent.indexOf("msie") != -1);
this.ie3 = (this.ie && (this.major == 2));
this.ie4 = (this.ie && (this.major >= 4));
this.op3 = (agent.indexOf("opera") != -1);
}
var is = new Is();
if (is.ie4){
do IE stuff
}
if (is.ns4) {
do netscape stuff
}
Obj = eval(
doc + '["btn"]' + sty);
Obj.width = available_width;
}
Hope this helps!
-Ray