javascript判断变量类型的自定义函数

通常用typeof来判断js变量的类型，但很多时候仅仅typeof满足不了要求的。

我写了一个自定义函数来做这个事，判断的比较全面了。

 

New

function varType(v){
  if ( typeof v=== "object" ){
    if (v=== null ) return 'null' ;
    if (v. constructor )
      return (v. constructor .toString()).match(/(?: )[/w/$]+/)[ 0 ];
    if ( typeof typeof2=== 'undefined' && window .execScript){
      window .execScript( 'Function vbsTypeName(o):vbsTypeName=TypeName(o):End Function' , 'vbscript' );
      window .execScript( 'function typeof2(o){return vbsTypeName(o)}' , 'jscript' );
    }
    if ( typeof typeof2!== 'undefined' ){
      return typeof2(v);
    }
    return "object" ;
  }
  return typeof v;
}

//对于普通js常量和js对象，各浏览器是基本一致的
alert (varType()); //undefined
alert (varType( 100 )); //number
alert (varType({})); //Object
alert (varType([])); //Array
alert (varType(/ /)); //RegExp
alert (varType( new Date ())); //Date
alert (varType( Date )); //function
alert (varType( Object )); //function
alert (varType( RegExp )); //function

//对于DOM对象，各浏览器可能会有不同值
alert (varType( window )); //IE:HTMLWindow2 FF:Window
alert (varType( document )); //IE:HTMLDocument FF:HTMLDocument
alert (varType( document .body)); //IE:HTMLBody FF:HTMLBodyElement
alert (varType( Option )); //IE:Object  FF:function
alert (varType( Image )); //IE:Object  FF:function
alert (varType( navigator )); //IE:DispHTMLNavigator FF:Navigator

//以下几个只适用于IE，其他内核浏览器不支持
alert (varType( ActiveXObject )); //IE:function
alert (varType( Enumerator )); //IE:function
alert (varType( new ActiveXObject ( "Scripting.Dictionary" ))); //IE:Dictionary
alert (varType( new Enumerator ())); //IE:Enumerator