python 常用函数（不定时更新）

1.遍历文件夹

 import os
 def FileList(rootDir):
     FL=[]
     for lists in os.listdir(rootDir):
         path=os.path.join(rootDir, lists)
         FL.append(path)

         if os.path.isdir(path):
             FileList(path)
     return FL

2.时间戳

import datetime

start=datetime.datetime.now()
print start
    。。。
end=datetime.datetime.now()
print end
print 'it costs ',end-start

3.合并多个TXT，生成新TXT。

import os
def MergeTXT(TXTlist,desTXT):
    f=open(desTXT,'w')
    for i in TXTlist:
        if isTXT(i):
            x = open(i, 'r')
            f.write(x.read())
            x.close()
        else:
            pass
    f.close()

def isTXT(filename):
    d=len(filename)
    e=filename.find('.txt',d-4,d)
    if e<0:
        return 0 #Not TXT
    else:
        return 1 #Is TXT