javascript judges the current browser version and judges the ie version

javascript determines the current browser version and determines the ie version:

<span style="font-size:18px;"> It is convenient to use again in the future: </span> 

<span style="font-size:18px;">1 , judgment ie Version </span> 

<pre name="code" class="javascript"><span style="font-size:18px;">//js Judge Ie  Version  
function IeVesion() { 
var Sys = {}; 
var ua = navigator.userAgent.toLowerCase(); 
var s; 
(s = ua.match(/msie ([\d.]+)/)) ? Sys.ie = s[1] : 
(s = ua.match(/firefox\/([\d.]+)/)) ? Sys.firefox = s[1] : 
(s = ua.match(/chrome\/([\d.]+)/)) ? Sys.chrome = s[1] : 
(s = ua.match(/opera.([\d.]+)/)) ? Sys.opera = s[1] : 
(s = ua.match(/version\/([\d.]+).*safari/)) ? Sys.safari = s[1] : 0; 
var ieversion; 
if (Sys.ie){ 
ieversion = parseInt(Sys.ie); 
if(ieversion<8) { 
alert(" Dear users! \n\n  You are currently using Internet Explorer Version is :"+Sys.ie+""); 
setIsTextReadOnly(true); 
} 
} else if (Sys.firefox) { 
ieversion = Sys.firefox; 
//setIsTextReadOnly(true); 
} else if (Sys.chrome) { 
ieversion = Sys.chrome; 
} else if (Sys.opera) { 
ieversion = Sys.opera; 
} else if (Sys.safari) { 
ieversion = Sys.safari; 
} 
} </span> 

2. Determine what kind of browser it is

<span style="font-size:18px;"> 
</span> 

<pre name="code" class="javascript"><span style="font-size:18px;">//js Judgment browser  
// Determine the browser version  
function getIEVersion() { 
 var OsObject = ""; 
 if(navigator.userAgent.indexOf("MSIE")>0) { 
 return "MSIE"; //IE 
 } else if(isFirefox=navigator.userAgent.indexOf("Firefox")>0){ 
 return "Firefox"; // Firefox  
 } else if(isSafari=navigator.userAgent.indexOf("Safari")>0) { 
 return "Safari"; //Ipad Browser  
 } else if(isCamino=navigator.userAgent.indexOf("Camino")>0){ 
 return "Camino"; 
 } else if(isMozilla=navigator.userAgent.indexOf("Gecko/")>0){ 
 return "Gecko"; 
 } 
}</span> 

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