Python/ArcPy取出指定文件夹中所有MDB文件并导出字段

#取出指定文件夹中所有MDB文件，读取其指定的FeatureClass，并将非空的GlobalID和SymbolRef记录到与FeatureClass同名的文本文件中

>>>target_folder = 'D:\T20161202'

... file_names=('BOUAN','BOULK','BOUNT','BOUPT','CTRLK','CTRPT','HYDAN','HYDLK','HYDNT','HYDPT','PIPAN','PIPLK','PIPNT','PIPPT','RESAN','RESLK','RESNT','RESPT','ROAAN','ROALK','ROANT','ROAPT','TERAN','TERLK','TERNT','TERPT','VEGAN','VEGLK','VEGNT','VEGPT')

... source_folder = 'D:\T20161221_SymbolRef'

... fields = ['GLOBALID','SymbolRef']

... expression = u"GLOBALID IS NOT NULL"

... for x in os.listdir(source_folder):

...     file_path = source_folder+'\\'+x

...     if os.path.isfile(file_path):

...         print file_path

...         mdb_paths= os.path.split(file_path)

...         mdb_names = mdb_paths[1].split('.')

...         if mdb_names[-1]=='mdb':

...             for file_name in file_names:

...                 feature_class = os.path.join( file_path,file_name)

...                 print feature_class

...                 result_path = target_folder+'\\'+file_name+'.txt'

...                 print result_path

...                 file_open = open(result_path,'a')

...                 if arcpy.Exists(feature_class):

...                     with arcpy.da.SearchCursor(feature_class,fields,where_clause = expression) as cursor:

...                         for row in cursor:

...                             if len(row[0])>0 and  len(row[1])>0:

...                                 a_row=u'{0}+{1}'.format(row[0],row[1])

...                                 print a_row

...                                 file_open.write(a_row)

...                                 file_open.write('\n')

...                 file_open.close()