How do I detect what browser is used to access my site?

Question

How do I detect what browser (IE, Firefox, Opera) the user is accessing my site with? Examples in Javascript, PHP, ASP, Python, JSP, and any others you can think of would b

Answer 1

A quick and dirty java servlet example

private String getBrowserName(HttpServletRequest request) {
    // get the user Agent from request header
    String userAgent = request.getHeader(Constants.BROWSER_USER_AGENT);
    String BrowesrName = "";
    //check for Internet Explorer
    if (userAgent.indexOf("MSIE") > -1) {
        BrowesrName = Constants.BROWSER_NAME_IE;
    } else if (userAgent.indexOf(Constants.BROWSER_NAME_FIREFOX) > -1) {
        BrowesrName = Constants.BROWSER_NAME_MOZILLA_FIREFOX;
    } else if (userAgent.indexOf(Constants.BROWSER_NAME_OPERA) > -1) {
        BrowesrName = Constants.BROWSER_NAME_OPERA;
    } else if (userAgent.indexOf(Constants.BROWSER_NAME_SAFARI) > -1) {
        BrowesrName = Constants.BROWSER_NAME_SAFARI;
    } else if (userAgent.indexOf(Constants.BROWSER_NAME_NETSCAPE) > -1) {
        BrowesrName = Constants.BROWSER_NAME_NETSCAPE;
    } else {
        BrowesrName = "Undefined Browser";
    }
    //return the browser name
    return BrowesrName;
}