Python8-24

#Open your images in binary mode and read them in as binary strings then
#save them in a list/dict/tuple , then pickle it.
>>> import Image, pickle, cStringIO
>>> i = open(‘c:/1.jpg‘, ‘rb‘)
>>> i.seek(0)
>>> w = i.read()
>>> i.close()
>>> dic =  {‘1‘:w,‘2‘:w,‘3‘:w,‘4‘:w}
>>> p = pickle.dumps(dic)
# storage would happen at this point

#Ok now you take your pickled string and unpickle your object and select
#the item you want and put it in a cStringIO or StringIO so we can open
#it directly with PIL.
# sometime in the future
>>> o = pickle.loads(p)
>>> one_im = o[‘1‘]
>>> c = StringIO.StringIO()
>>> c.write(one_im)
>>> c.seek(0)
>>> im = Image.open(c)
>>> im.show()

#Alternatively you can create a StringIO object and pickle that in your
#dictionary so you can just load it later with PIL.

#拆分目录与文件
os.path.split()
#连接目录与文件
os.path.join(path,name)
#返回文件名
os.path.basename(path)
#返回路径
os.path.dirname(path)

import os,sys
def listdir(dir,file):
    file.write(dir + ‘\n‘)
    fielnum = 0
    list = os.listdir(dir)  #列出目录下的所有文件和目录
    for line in list:
        filepath = os.path.join(dir,line)
        if os.path.isdir(filepath):  #如果filepath是目录，则再列出该目录下的所有文件
            myfile.write(‘   ‘ + line + ‘\\‘+‘\n‘)
            for li in os.listdir(filepath):
                myfile.write(‘     ‘+li + ‘\n‘)
                fielnum = fielnum + 1
        elif os.path:   #如果filepath是文件，直接列出文件名
            myfile.write(‘   ‘+line + ‘\n‘)
            fielnum = fielnum + 1
    myfile.write(‘all the file num is ‘+ str(fielnum))
dir = raw_input(‘please input the path:‘)
myfile = open(‘list.txt‘,‘w‘)

‘‘‘os.walk方法

os模块提供的walk方法很强大，能够把给定的目录下的所有目录和文件遍历出来。

方法：os.walk(path),遍历path，返回一个对象，他的每个部分都是一个三元组,(‘目录x‘，[目录x下的目录list]，目录x下面的文件)
‘‘‘
import os
def walk_dir(dir,fileinfo,topdown=True):
    for root, dirs, files in os.walk(dir, topdown):
        for name in files:
            print(os.path.join(name))
            fileinfo.write(os.path.join(root,name) + ‘\n‘)
        for name in dirs:
            print(os.path.join(name))
            fileinfo.write(‘  ‘ + os.path.join(root,name) + ‘\n‘)
dir = raw_input(‘please input the path:‘)
fileinfo = open(‘list.txt‘,‘w‘)
walk_dir(dir,fileinfo)

‘‘‘topdown决定遍历的顺序，如果topdown为True，则先列举top下的目录，然后是目录的目录，依次类推，反之，则先递归列举出最深层的子目录，然后是其兄弟目录，然后子目录。
‘‘‘