javascript ext 闭包

field = new Ext.form.fileHtml(
        {
         fieldLabel : record.get('displayname'),
         labelStyle : 'color:blue;text-align:right;width:190;',
         name : nameUse,
         id : record.get('uuid'),
         width : 400,
         browsFile :
                                            function() {
                            return function(){   browsFileHtml(field)
                            }
                        } ,
         deleteFile : deleteFile,
         hidden : hiddenflg,
         //disabled : readOnly,
         height : 200,
         filePath : record.get('filePath')
        });