shelve,cPickle模組

close() 關閉檔案物件

flush() 重新整理檔案的緩衝區。緩衝區包含等待寫入或檔案中讀取的資訊。“重新整理“就是執行實際的讀取或寫入操作

isatty() 如果檔案物件是tty(終端）裝置，就返回1

read([size]) 從檔案中讀取資料。

readline([size]) 從檔案中讀取一行

readlines([size]) 從檔案中讀取多行

seek(offset[,location]) 使檔案位置移動offset個位元組。如果沒有指定location,檔案位置從檔案起始處移動。如是指定了location,就從指定位置移動。

tell() 返回檔案的當前位置

write(output) 將字串output寫入檔案

writeline(outputlist) 將outputlist中的每個字串寫入檔案

writelines() 寫入多行資料

一.建立順序訪問檔案

寫入檔案

import sys

try:

file=open("client.dat","w")

except IOError,message:

print >> sys.stderr, "File could not be opened",message

sys.exit(1)

print "Enter the accout,name and age."

while 1:

try:

accountline=raw_input("?")

except EOFError:

break

else:

print >>file,accountline

file.close()

讀取資料

import sys

try:

file=open("client.dat","r")

except IOError:

print >> sys.stderr, "File could not be opened"

sys.exit(1)

records=file.readlines()

print "Account",ljust(10)

print "Name",ljust(10)

print "age",ljust(10)

for record in records:

fields=record.split()

print fields[0].ljust(10),

print fields[1].ljust(10),

print fields[2].ljust(10),

file.close()

shelve模組應用

模擬隨機訪問檔案：

import sys

import shelve

try:

coutcredit=shelve.open("credit.dat")

except IOError:

print >> sys.stderr,"File could not be opened"

sys.exit(1)

print "Enter account number (1 to 100,0 to end input)"

while 1:

accountNumber=int(raw_input("\nEnter account number\n?"))

if 0 < accountNumber <= 100:

print "Enter lastname, Firetname,balance"

currentData=raw_input("?")

outCredit[str{accountNumber)]=currentDdata.split()

elif accountNumber==0:

break

outCredit.close()

cPickle模組應用

注：cPickle模組的執行效率高於pickle

寫檔案

import sys

import cPickle

try:

coutcredit=open("credit.dat","w")

except IOError:

print >> sys.stderr,"File could not be opened"

sys.exit(1)

print "Enter account number (1 to 100,0 to end input)"

inputlist=[]

while 1:

try:

accountline=raw_input("?")

except EOFErrot:

break

else:

inputlist.append(accountline.split())

cPickle.dump(inputlist,outCredit)

outCredit.close()

讀出資料

import sys

import cPickle

try:

outcredit=open("credit.dat","r")

except IOError:

print >> sys.stderr,"File could not be opened"

sys.exit(1)

records=cPickle.load(outcredit)

outcredit.close()

for record in records:

print record[0].ljust(15),

print record[1].ljust(10),

print record[2].ljust(20)