Python string and file operations Common function analysis

This article analyzes the Python string and file operations commonly used functions. Share to everyone for your reference. Specific as follows:

#-*-Coding:utf-8-*-' Created on 2010-12-27@author:sumory ' ' Import itertoolsdef a_containsanyof_b (seq,aset): ' Judgment s Whether the EQ contains one or more items in the Aset seq can be a string or list aset should be a string or list "for item in Itertools.ifilter (ASET.__CONTAINS__,SEQ): retur N True return falsedef A_allin_b (seq,aset): "' Determines whether all items in the SEQ are in aset seq can be a string or the list aset should be a string or list ' for item in SE ' Q:IF Item not in Aset:return False return truedef a_containsall_b (seq,aset): "' Determine if SEQ contains all items in Aset seq can be a character The string or list aset should be either strings or a list of any set objects a,a.difference (b) is equivalent to A-set (b), which returns all elements in a that are not part of B ' return not set (Aset). Difference (s EQ) Import string# generates a reusable string of all characters Sumory_allchars=string.maketrans ("', ') def makefilter (keep):" ' Returns a function,    This function takes a source string as a parameter \ and returns a partial copy of the string \ This copy only includes characters in Keep, keep must be a normal string \ Call Example: Makefilter (' ABCA ') (' abcdefgh ijkal CBA ') \ Keep the preceding character in the string that follows the ABC a CBA "#按照sumory_allchars规则剔除sumory_allchars字符串中的keep里的字符 #这里得到keep在sumory_allchars的补集 Dele Techars=sumory_allchars.translate (Sumory_alLchars,keep) #生成并返回需要的过滤函数 (as closure) def Realdelete (SOURSESTR): Return Soursestr.translate (Sumory_allchars,deletechars)      return realdeletedef List_removesame (list): "Delete duplicates in list" ' templist=["for C in List:if C is not templist: Templist.append (c) return templistdef re_indent (str,numberofspace): ' Indent \ Divide string str by line break and add numberofspace space before each sentence \ re-combined into string ' ' ' spaces=numberofspace* ' ' Lines=[spaces+line.strip () for line in Str.splitlines ()] return ' \ n '. Join (lines) def replace_strby_dict (soursestr,dict,marker= ' "', Safe=false): ' Use a dictionary to replace the corresponding value of the marker package in the source string #如果safe为True, If the key is not found in the dictionary, do not replace if Safe:def lookup (W): Return Dict.get (W,w.join (marker*2)) #w. Join (MARKER*2) with marker package W #如果saf   If E is false, throw exception when key is not found in the dictionary \ #若将dict [w] to Dict.get (W) to return none Else:def lookup (W): Return dict[w] #根据marker切分源字符串 Splitparts=soursestr.split (marker) #取出切分后的奇数项 #因为切分后, the item in the source string in the list marker the parcel must be in the base part #就算是 the string "First" s is one "#分割后 The No. 0 item is an empty string, and the 1th item is first Splitparts[1::2]=map(Lookup,splitparts[1::2]) return ". Join (SplitParts) def simply_replace_strby_dict (soursestr,dict,safe=true):" Replace the substring of the $ tag in soursestr original string with dict content \ dict= {' name ': ' sumory ', ' Else ': ' Default '} $$5, $ $else, default ${name} ' s me Thod, Sumory ' s method ' style=string.     Template (SOURSESTR) #如果safe, can not be found in the dict will not replace, so keep the original string if Safe:return Style.safe_substitute (dict) #false, can not find to throw exception else: Return Style.substitute (dict) ################################################# #def Scanner (object,linehandler): "  Use the Linehandler method to traverse every item of the object "for lines in Object:linehandler" (line) def printfilelines (path): "reads the file screen of the path path to print" Fileobject=open (path, ' R ') #open不用放到try里 Try:for line in Fileobject:print (Line.rstrip (' \ n ')) finally:fileob    Ject.close () def writelisttofile (path,ilist): Fileobject=open (Path, ' W ') Try:fileobject.writelines (IList) Finally: Fileobject.close () Import zipfiledef listzipfilesinfo (path): Z=zipfile. ZipFile (path, ' R ') try:for FilenamE in Z.namelist (): bytes=z.read (filename) print (' file:%s size:%s '% (Unicode (filename, ' cp936 '). Decode (' utf-8 '), le N (bytes))) Finally:z.close () Import os,fnmatchdef list_all_files (root,patterns= ' * ', single_level=false,yield_  Folders=false): "List directory (or files under its subdirectories)" #分割模式到列表 patterns=patterns.split (';') For path,subdirs,files in Os.walk (root): if Yield_folders:files.extend (subdirs) Files.sort () for name in fi Les:for Pat in Patterns:if Fnmatch.fnmatch (name, Pat): Yield '/'. Join (Unicode (Os.path.join (Path,nam e), ' cp936 '). Split (' \ \ ')) Break if Single_level:breakdef swapextensions (root,before,after): If before[:1 ]!= '. ': before= '. ' +before Extensionlen=-len (before) if after[:1]!= '. ': after= '. ' +after for path,subdirs,files in Os.walk (root): For oldfile in Files:if oldfile[extensionlen:]==before:o Ldfile=os.path.join (path,oldfile) newfile=oldfile[:extensionlen]+after os.rename (Oldfile, newFile 

Hopefully this article will help you with Python programming.

