DirectoryUtility = {
    // function getCurrentDirectory: returns currentDirectory path 
    // with a trailing backslash.
    getCurrentDirectory : function ( ) {
        var scriptFullName = WScript.ScriptFullName;
        var scriptName = WScript.ScriptName;
        return scriptFullName.substr ( 0, scriptFullName.lastIndexOf ( scriptName ) );
    }
}

/* 用法 */
DirectoryUtility.getCurrentDirectory ( );
//javascript/4