#!/usr/bin/env python
with open('pi') as file_object:
  contents = file_object.read()
  print(contents)
 
===================================
3.1415926
 5212533
 2324255

#!/usr/bin/env python
filename = 'pi'
with open(filename) as file_object:
  for line in file_object:
    print(line)
 
===================================
3.1415926
 5212533
 2324255

#!/usr/bin/env python
filename = 'pi'
with open(filename) as file_object:
  for line in file_object:
    print(line.rstrip())
==================
3.1415926
 5212533
 2324255

#!/usr/bin/env python
filename = 'pi'
with open(filename) as file_object:
  lines = file_object.readlines()   #readlines()方法是從文件中讀取每一行，并將其存儲(chǔ)在一個(gè)列表中
for line in lines:
  print(line.rstrip())
==============================
3.1415926
 5212533
 2324255

#!/usr/bin/env python
filename = 'pi'
with open(filename) as file_object:
  lines = file_object.readlines()
pi_string = ''
for line in lines:
  pi_string += line.strip()
print(pi_string)
print(len(pi_string))
========================================
3.141592652125332324255
23

#!/usr/bin/env python
filename = 'programming.txt'
with open(filename,'w') as file_object:
  file_object.write("I love programming!")

#!/usr/bin/env python
filename = 'programming.txt'
with open(filename,'w') as file_object:
  file_object.write("I love programming!\n")
  file_object.write("yes!\n")

#!/usr/bin/env python
filename = 'pi'
with open(filename,'a') as file_object:
  file_object.write("I love programming!\n")
  file_object.write("yes!\n")

#!/usr/bin/env python
 
try:
  print(5/0)
except ZeroDivisionError:
  print("You cant divide by zero!")

try:
<語(yǔ)句>    #運(yùn)行別的代碼
except <名字>：
<語(yǔ)句>    #如果在try部份引發(fā)了'name'異常
except <名字>，<數(shù)據(jù)>:
<語(yǔ)句>    #如果引發(fā)了'name'異常，獲得附加的數(shù)據(jù)
else:
<語(yǔ)句>    #如果沒(méi)有異常發(fā)生

#!/usr/bin/python
# -*- coding: UTF-8 -*-
try:
  fh = open("testfile", "w")
  fh.write("這是一個(gè)測(cè)試文件，用于測(cè)試異常!!")
except IOError:
  print "Error: 沒(méi)有找到文件或讀取文件失敗"
else:
  print "內(nèi)容寫(xiě)入文件成功"
  fh.close()

$ python test.py 
內(nèi)容寫(xiě)入文件成功
$ cat testfile    # 查看寫(xiě)入的內(nèi)容
這是一個(gè)測(cè)試文件，用于測(cè)試異常!!

#!/usr/bin/python
# -*- coding: UTF-8 -*-

try:
  fh = open("testfile", "w")
  fh.write("這是一個(gè)測(cè)試文件，用于測(cè)試異常!!")
except IOError:
  print "Error: 沒(méi)有找到文件或讀取文件失敗"
else:
  print "內(nèi)容寫(xiě)入文件成功"
  fh.close()

chmod -w testfile

$ python test.py 
Error: 沒(méi)有找到文件或讀取文件失敗