Detect browser typeTag(s): Varia


Detecting if a feature is present or not
We test for a known feature to decide the browser type.
ns = (document.layers) ? true : false;
ie = (document.all) ? true : false;
ff = document.getElementById? true : false;
if (ie) document.write("Internet Explorer");
else if (ff) document.write("Firefox");
else if (ns) document.write("Netscape");
else document.write("Unknown browser !!!");
With this browser, this code gives :
Use a conditionnal comment
See this HowTo
Use the browser name
This technique is not very good because a browser can alter its name to allow a better compatibility.
<HTML>
<HEAD>
<SCRIPT LANGUAGE= "JavaScript">
function isNetscape(v) {
  /*
  ** Check if the browser is Netscape compatible
  **    v  version number
  ** returns  true if Netscape and version equals or greater
  */
  return isBrowser("Netscape", v);
  }

function isMicrosoft(v) {
  /*
  ** Check if the browser is Microsoft Internet Explorer compatible
  **    v  version number
  ** returns  true if MSIE and version equals or greater
  */
  return isBrowser("Microsoft", v);
  }

function isBrowser(b,v) {
  /*
  ** Check if the current browser is compatible
  **  b  browser name
  **  v  version number (if 0 don't check version)
  ** returns true if browser equals and version equals or greater
  */
  browserOk = false;
  versionOk = false;

  browserOk = (navigator.appName.indexOf(b) != -1);
  if (v == 0) versionOk = true;
  else  versionOk = (v <= parseInt(navigator.appVersion));
  return browserOk && versionOk;
  }
</SCRIPT></HEAD><BODY><FORM>
<INPUT TYPE="button"
       VALUE="Test for Netscape 4"
       onClick="alert(isBrowser('Netscape', 4));">
<INPUT TYPE="button"
       VALUE="Test for IE3"
       onClick="alert(isBrowser('Explorer', 0));">
</FORM></BODY></HTML>
For more complete script to detect browser version, check the Netscape site
blog comments powered by Disqus