detect IE and version number through injected conditional comments

detect IE and version number through injected conditional comments.js

//detect Internet Explorer and version number through injected conditional comments (no UA detect, no need for cond. compilation / jscript check)

//version arg is for IE version (optional)
//comparison arg supports 'lte', 'gte', etc (optional)

var isIE = (function(doc, undefined){
  
  var cache = {},
    elem;
  
  return function( version, comparison ) {
    if(/*@cc_on!@*/true){return false;}

    var key = [ comparison || '', 'IE', version || '' ].join(' ');
    
    if (!(key in cache)) {
      elem = elem || doc.createElement( 'B' );
      elem.innerHTML = '<!--[if '+ key +']><b></b><![endif]-->';
      cache[ key ] = !!elem.getElementsByTagName( 'b' ).length;
    }
    
    return cache[ key ];
  };
  
}(document));

//minified:
var isIE=(function(doc){var cache={},elem;return function(version,comparison){if(/*@cc_on!@*/true){return false;}var key=[comparison||"","IE",version||""].join(" ");if(!(key in cache)){elem=elem||doc.createElement("B");elem.innerHTML="<!--[if "+key+"]><b></b><![endif]-->";cache[key]=!!elem.getElementsByTagName("b").length;}return cache[key];};}(document));
		
//is it IE?		
isIE(); 

//is it IE6?
isIE(6);

//is it less than or equal to IE 7?
isIE(7,'lte');