浏览器检测脚本

检测脚本源码：

/*
 *fileName:detect.js
 */
var sUserAgent = navigator.userAgent;
var fAppVersion = parseFloat(navigator.appVersion);
function compareVersions(sVersion1, sVersion2) {
	var aVersion1 = sVersion1.split(".");
	var aVersion2 = sVersion2.split(".");
	if (aVersion1.length > aVersion2.length) {
		for (var i = 0; i < aVersion1.length - aVersion2.length; i++) {
			aVersion2.push("0");
		}
	} else {
		if (aVersion1.length < aVersion2.length) {
			for (var i = 0; i < aVersion2.length - aVersion1.length; i++) {
				aVersion1.push("0");
			}
		}
	}
	for (var i = 0; i < aVersion1.length; i++) {
		if (aVersion1[i] < aVersion2[i]) {
			return -1;
		} else {
			if (aVersion1[i] > aVersion2[i]) {
				return 1;
			}
		}
	}
	return 0;
}
//---------------------------------------------------------检测浏览器

//检测是否是Opera浏览器
var isOpera = sUserAgent.indexOf("Opera") > -1;
var isMinOpera4 = isMinOpera5 = isMinOpera6 = isMinOpera7 = isMinOpera7_5 = false;
if (isOpera) {
	var fOperaVersion;
	if (navigator.appName == "Opera") {
		fOperaVersion = fAppVersion;
	} else {
		var reOperaVersion = new RegExp("Opera (\\d+\\.\\d+)");
		reOperaVersion.test(sUserAgent);
		fOperaVersion = parseFloat(RegExp["$1"]);
	}
	isMinOpera4 = fOperaVersion >= 4;
	isMinOpera5 = fOperaVersion >= 5;
	isMinOpera6 = fOperaVersion >= 6;
	isMinOpera7 = fOperaVersion >= 7;
	isMinOpera7_5 = fOperaVersion >= 7.5;
}
//检测是否是Konqueror/Safari浏览器
var isKHTML = sUserAgent.indexOf("KHTML") > -1 || sUserAgent.indexOf("Konqueror") > -1 || sUserAgent.indexOf("AppleWebKit") > -1;
var isMinSafari1 = isMinSafari1_2 = false;
var isMinKonq2_2 = isMinKonq3 = isMinKonq3_1 = isMinKonq3_2 = false;
if (isKHTML) {
	isSafari = sUserAgent.indexOf("AppleWebKit") > -1;
	isKonq = sUserAgent.indexOf("Konqueror") > -1;
	if (isSafari) {
		var reAppleWebKit = new RegExp("AppleWebKit\\/(\\d+(?:\\.\\d*)?)");
		reAppleWebKit.test(sUserAgent);
		var fAppleWebKitVersion = parseFloat(RegExp["$1"]);
		isMinSafari1 = fAppleWebKitVersion >= 85;
		isMinSafari1_2 = fAppleWebKitVersion >= 124;
	} else {
		if (isKonq) {
			var reKonq = new RegExp("Konqueror\\/(\\d+(?:\\.\\d+(?:\\.\\d)?)?)");
			reKonq.test(sUserAgent);
			isMinKonq2_2 = compareVersions(RegExp["$1"], "2.2") >= 0;
			isMinKonq3 = compareVersions(RegExp["$1"], "3.0") >= 0;
			isMinKonq3_1 = compareVersions(RegExp["$1"], "3.1") >= 0;
			isMinKonq3_2 = compareVersions(RegExp["$1"], "3.2") >= 0;
		}
	}
}
//检测是否是IE浏览器
var isIE = sUserAgent.indexOf("compatible") > -1 && sUserAgent.indexOf("MSIE") > -1 && !isOpera;
var isMinIE4 = isMinIE5 = isMinIE5_5 = isMinIE6 = false;
if (isIE) {
	var reIE = new RegExp("MSIE (\\d+\\.\\d+);");
	reIE.test(sUserAgent);
	var fIEVersion = parseFloat(RegExp["$1"]);
	isMinIE4 = fIEVersion >= 4;
	isMinIE5 = fIEVersion >= 5;
	isMinIE5_5 = fIEVersion >= 5.5;
	isMinIE6 = fIEVersion >= 6;
}
//检测是否是Mozilla浏览器
var isMoz = sUserAgent.indexOf("Gecko") > -1 && !isKHTML;
var isMinMoz1 = sMinMoz1_4 = isMinMoz1_5 = false;
if (isMoz) {
	var reMoz = new RegExp("rv:(\\d+\\.\\d+(?:\\.\\d+)?)");
	reMoz.test(sUserAgent);
	isMinMoz1 = compareVersions(RegExp["$1"], "1.0") >= 0;
	isMinMoz1_4 = compareVersions(RegExp["$1"], "1.4") >= 0;
	isMinMoz1_5 = compareVersions(RegExp["$1"], "1.5") >= 0;
}
//检测是否是Netscape Communicator 4.x浏览器
var isNS4 = !isIE && !isOpera && !isMoz && !isKHTML && (sUserAgent.indexOf("Mozilla") == 0) && (navigator.appName == "Netscape") && (fAppVersion >= 4 && fAppVersion < 5);
var isMinNS4 = isMinNS4_5 = isMinNS4_7 = isMinNS4_8 = false;
if (isNS4) {
	isMinNS4 = true;
	isMinNS4_5 = fAppVersion >= 4.5;
	isMinNS4_7 = fAppVersion >= 4.7;
	isMinNS4_8 = fAppVersion >= 4.8;
}
//---------------------------------------------------------检测操作系统
var isWin = (navigator.platform == "Win32") || (navigator.platform == "Windows");
var isMac = (navigator.platform == "Mac68K") || (navigator.platform == "MacPPC") || (navigator.platform == "Macintosh");
var isUnix = (navigator.platform == "X11") && !isWin && !isMac;
var isWin95 = isWin98 = isWinNT4 = isWin2K = isWinME = isWinXP = false;
var isMac68K = isMacPPC = false;
var isSunOS = isMinSunOS4 = isMinSunOS5 = isMinSunOS5_5 = false;
//检测Windows操作系统
if (isWin) {
	isWin95 = sUserAgent.indexOf("Win95") > -1 || sUserAgent.indexOf("Windows 95") > -1;
	isWin98 = sUserAgent.indexOf("Win98") > -1 || sUserAgent.indexOf("Windows 98") > -1;
	isWinME = sUserAgent.indexOf("Win 9x 4.90") > -1 || sUserAgent.indexOf("Windows ME") > -1;
	isWin2K = sUserAgent.indexOf("Windows NT 5.0") > -1 || sUserAgent.indexOf("Windows 2000") > -1;
	isWinXP = sUserAgent.indexOf("Windows NT 5.1") > -1 || sUserAgent.indexOf("Windows XP") > -1;
	isWinNT4 = sUserAgent.indexOf("WinNT") > -1 || sUserAgent.indexOf("Windows NT") > -1 || sUserAgent.indexOf("WinNT4.0") > -1 || sUserAgent.indexOf("Windows NT 4.0") > -1 && (!isWinME && !isWin2K && !isWinXP);
}
//检测Macintosh操作系统
if (isMac) {
	isMac68K = sUserAgent.indexOf("Mac_68000") > -1 || sUserAgent.indexOf("68K") > -1;
	isMacPPC = sUserAgent.indexOf("Mac_PowerPC") > -1 || sUserAgent.indexOf("PPC") > -1;
}
//检测Unix操作系统
if (isUnix) {
	isSunOS = sUserAgent.indexOf("SunOS") > -1;
	if (isSunOS) {
		var reSunOS = new RegExp("SunOS (\\d+\\.\\d+(?:\\.\\d+)?)");
		reSunOS.test(sUserAgent);
		isMinSunOS4 = compareVersions(RegExp["$1"], "4.0") >= 0;
		isMinSunOS5 = compareVersions(RegExp["$1"], "5.0") >= 0;
		isMinSunOS5_5 = compareVersions(RegExp["$1"], "5.5") >= 0;
	}
}

示例：

<html>
    <head>
        <title>Login</title>
        <script type="text/javascript" src="detect.js"></script>
        <script type="text/javascript">
            window.onload = function () {
                if ((isMinIE5_5 && isWin) || (isMinMoz1 && isUnix) 
                   || (isMinSafari1 && isMac)) {

                  document.getElementById("divLogin").style.visibility = "visible";
                  document.getElementById("divError").style.visibility = "hidden"
                }
            };
        </script>
    </head>
    <body>
        <form method="post" action="DoLogin.jsp">
            <div style="border: 2px dashed blue; background-color: #dedede; height: 300px; padding: 10px">
                <div id="divError" style="position: absolute; left: 20px; top: 100px; ">
                    This Web application requires one of the following:
                    <ul>
                        <li>Internet Explorer 5.5 or higher for Windows</li>
                        <li>Mozilla 1.0 or higher for Unix</li>
                        <li>Safari 1.0 or higher for Macintosh</li>
                    </ul>
                    <noscript><!-- 不支持JavaScript时显示 -->
                      <p>This Web application also requires JavaScript (if you are using one of the above browsers, make sure that JavaScript is enabled).</p>
                    </noscript>
                </div>
                <div id="divLogin" style="position: absolute; left: 20px; top: 100px; visibility: hidden">
                    <table border="0" width="100%" height="100%"><tr><td align="center">
                    <table border="0">
                        <tr>
                            <td>Username:</td><td><input type="text" name="txtUsername" /></td>
                        </tr>
                        <tr>
                            <td>Password:</td><td><input type="password" name="txtPassword" /></td>
                        </tr>
                        <tr>
                            <td>&nbsp;</td><td><input type="Submit" value="Login" /></td>
                        </tr>
                    </table>
                </td></tr></table>
                </div>
            </div>
        </form>
    </body>
</html>