Python檔案和異常的學習

學習**

with open('pi_digits.txt') as file_object:

contents=file_object.read()
print(contents)

3.1415926535

8979323846
2643383279

filename='e:\code\python\pi_digits.txt'

with open(filename) as file_object:
for line in file_object:
print(line)

3.1415926535

8979323846
2643383279

filename='pi_digits.txt'

with open(filename) as file_object:
lines=file_object.readlines()
for line in lines:
print(line.rstrip())

pi_string=''

for line in lines:
pi_string+=line.rstrip()
print(pi_string)
print(len(pi_string))

3.141592653589793238462643383279

32

filename='programming.txt'

with open(filename,'w') as file_object:
file_object.write("i love programming.")
file_object.write("i love python")

i love programming.i love python

with open(filename,'a') as file_object:

file_object.write("i also love finding meaning in large datasets.\n")

try:

print(8/0)
except zerodivisionerror:
print("zerodivisionerror!!!")

zerodivisionerror!!!

print("else**塊")

print("divide.")
print("enter 'q' to quit!")
while true:
first_number=input("\nfirst number.")
if first_number=='q':
break
second_number=input("\nsecond number.")
try:
answer=int(first_number)/int(second_number)
except zerodivisionerror:
print("zerodivisionerror!")
else:
print(answer)

divide.

enter 'q' to quit!
first number.3
second number.1
3.0first number.3
second number.0
zerodivisionerror!
first number.q

filename='party.txt'

with open(filename) as f_obj:
contents=f_obj.read()
words=contents.split()
print(len(words))

154565

def count_words(filename):

try:
with open(filename) as f_obj:
contents=f_obj.read()
except filenotfounderror:
pass
else:
words=contents.split()
print(filename+" has about "+ str(len(words)))
filenames=['pi_digits.txt','alice.txt','party.txt']
for f in filenames:
count_words(f)

pi_digits.txt has about 3

party.txt has about 154565

import json

number=[2,3,5,7,11,13]
filename="number.json"
with open(filename,'w') as f_obj:
json.dump(number,f_obj)
with open(filename) as f_obj:
numbers=json.load(f_obj)
print(numbers)

username=input("what is your name?")

filename='username.json'
with open(filename,'w') as f:
json.dump(username,f)
with open(filename) as f:
username=json.load(f)
print(username)

what is your name?yang

yang

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