How to detect browser agent?

I am using JSP and I added the following code to the JSP to determine the broswer type.  If its IE then display one CSS else Netscape and display another CSS.

Its not working! Can some one please help?

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html>
<head>

<%
String propName, propValue;
boolean isIE, isNetscape;
propName = "User-Agent";
propValue = request.getHeader(propName);

if ( propName.indexOf("Netscape") == 0 ) {
  isNetscape = true;
  isIE = false;
}
%>
<link rel="stylesheet" type="text/css" href="unix.css">
<%
else {
isIE = true;
isNetscape = false;
}
%>
<link rel="stylesheet" type="text/css" href="win_ie.css">

</head>

<title> TEST </title>
<body bgcolor=white>
Test to check broswer version
</body>
</html>
sdesarAsked:
Who is Participating?
 
TimYatesConnect With a Mentor Commented:
Try putting

<H1><%= request.getHeader(propName); %></H1>

inside the body of your jsp...

What does that show for Netscape and for IE?

I am guessing that neither of them has the word "Netscape" at the start...

You could also try changing:

if ( propName.indexOf("Netscape") == 0 ) {

to

if ( propName.indexOf("Netscape") > -1 ) {

As that sould fix it (so long as Netscape actually does have the word "Netscape" somewhere in it's User-Agent string...

Good luck!!

Tim.
0
 
Igor BazarnyCommented:
Hi,

Why your links to stylesheet are out of if branches? As far as I understand JSP, this should lead to uncompilable java code:

<%
[declarations skipped]
if ( propName.indexOf("Netscape") == 0 ) {
   isNetscape = true;
   isIE = false;
}
%>
<-- Here you effectively end if because next statement will
translate into output to responce stream -->
<link rel="stylesheet" type="text/css" href="unix.css">
<%
else {
// Here yor should get 'else without if' error message
  isIE = true;
  isNetscape = false;
}
%>
<-- and even if I'm wrong, following link will be in responce in any case.
What is effect of 2 stylesheets? -->
<link rel="stylesheet" type="text/css" href="win_ie.css">

Regards,
Igor Bazarny
Brainbench MVP for Java 1
www.brainbench.com
0
 
sdesarAuthor Commented:
I am fairly new to JSPs.
i have 2 style-sheets. One for IE and one for Netscape.
How should I modify the above code then to
detect what browser the user is using and display the style-sheet accordingly?

I think I am missing an include... where does request.getheader come from?  which library?

help Please!
0
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TimYatesCommented:
Move the links inside the if statement braces:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html>
<head>

<%
String propName, propValue;
boolean isIE, isNetscape;
propName = "User-Agent";
propValue = request.getHeader(propName);

if ( propName.indexOf("Netscape") == 0 ) {
 isNetscape = true;
 isIE = false;
%>
<link rel="stylesheet" type="text/css" href="unix.css">
<%
}
else
{
isIE = true;
isNetscape = false;
%>
<link rel="stylesheet" type="text/css" href="win_ie.css">
<%
}
%>

</head>

<title> TEST </title>
<body bgcolor=white>
Test to check broswer version
</body>
</html>
0
 
sdesarAuthor Commented:
Here's my code :- It seems to be picking the else part of the CSS for both IE and Netscape.  It seems the code is not being recognised.  When I vire the code in the browser IE oe Netscape the following appears-
<link rel="stylesheet" type="text/css" href="/gts/jsp/win_ie.css">

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" "http://www.w3.org/TR/REC-html40/loose.dtd">
<html>
<head>

<%
String propName, propValue;
boolean isIE, isNetscape;
propName = "User-Agent";
propValue = request.getHeader(propName);

if ( propName.indexOf("Netscape") == 0 ) {
  isNetscape = true;
  isIE = false;
  out.println ( "<link rel=\"stylesheet\" type=\"text/css\" href=\"/gts/jsp/unix.css\">" );
}
else {
  out.println ( "<link rel=\"stylesheet\" type=\"text/css\" href=\"/gts/jsp/win_ie.css\">" );

}
%>
</head>

<title> TEST </title>
<body bgcolor=white>

<table border=0 cellspacing=0 cellpadding=0 width="170" summary="Left Contextual Navigation Table" >
  <tr>
  <td NOWRAP width="10"></td>
  <td NOWRAP width="10"></td>
  <td NOWRAP width="130"></td>
  <td NOWRAP width="10"></td>
  <td NOWRAP width="10"></td>
  </tr>
<tr>
    <td valign=TOP colspan="2" width="20" bgcolor="#336699"><font size="3"><img src="/gts/jsp/images/tl_navcorner_20.gif" alt="" border=0 height=20 width=20></font></td>
    <th align=CENTER NOWRAP width="130" bgcolor="#336699" class="menu_header" >
          <font color="#FFFFFF" size="3" class="menu_header">submit </font> </th>
    <td valign=TOP colspan="2" width="20" bgcolor="#336699"><font size="3"><img src="/gts/jsp/images/tr_navcorner_20.gif" alt="" border=0 height=20 width=20></font></td>
  </tr>
<tr> </tr>
</table>
<form accept-charset="UNKNOWN" method="post"
        action="/gts/servlet/GServlet/newissue">

<script>
alert (' entered ' );

</script>
     
     <p class="paragraph"> TEST THE PARAGRAPH </p>
   



<br>
<h>Thank You !   </h>


</body>



HELP PLEASE!

</html>
0
 
TimYatesCommented:
PS:  Phew what a lot of effort for 10 points ;-) ;-)

Hee hee!!  The cheek :-)

Good luck again!!!
0
 
sdesarAuthor Commented:
I had to check for the propValue!
 and > -1 worked!
Thanks a million!
0
 
sdesarAuthor Commented:
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0
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