js中activeXString是什么

Question

在代码：

function createXHR(){

  if(typeof XMLHttpRequest !="undefined"){

  return new XMLHttpRequest(); 

}else if(typeof ActiveXObject !="undefined"){

   if(typeof arguments.callee.activeXString !="string"){

   var versions = ["MSXML2.XMLHttp.6.0","MSXML2.XMLHttp.3.0","MSXML2.XMLHttp"];

   var i,len;

   for (i=0,len=versions.length;i<len;i++){

   try{

   new ActiveXObject(versions[i]);

    arguments.callee.activeXString = versions[i];

    break;

}catch(ex){}

}

}

return new ActiveXObject(arguments.callee.activeXString);

}else{

throw new Error("No XHR object available");

}

}

在上述代码中activeXString是什么呢

Answer 1

function Foo() {//&nbsp;do&nbsp;something;//&nbsp;arguments.callee.activeXString&nbsp;===&nbsp;'foo';};Foo.activeXString = 'foo';