Python學習筆記 Day11 檔案和異常

逐行讀取

file_name =

"pi_digits.txt"
with
open
(file_name)
as file_object:
for line in file_object:
print
(line.rstrip(
))

file_name =

"pi_million_digits.txt"
with
open
(file_name)
as file_object:
lines = file_object.readlines(
) pi_string =
''for line in lines:
pi_string += line.rstrip(
)print
(pi_string)
print
(len
(pi_string)
)

filename =

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

異常

try

: answer =
int(first_number)
/int
(second_number)
except zerodivisionerror:
print
("you can't divide bu 0!"
)else
:print
(answer)

filename =

'alice.txt'
try:
with
open
(filename)
as f_obj:
contents = f_obj.read(
)except filenotfounderror:
msg =
"sorry, the file "
+ filename +
" does not exist."
print
(msg)
else
:#計算檔案大致包含多少個單詞
words = contents.split(
) num_words =
len(words)
print
("the file "
+ filename +
" has about "
+str
(num_words)
+" words."
)

#定義計算檔案有多少個單詞的函式

defcount_words
(filename)
:try
:with
open
(filename)
as f_obj:
contents = f_obj.read(
)except filenotfounderror:
msg =
"sorry, the file "
+ filename +
" does not exist."
print
(msg)
else
:#計算檔案大致包含多少個單詞
words = contents.split(
) num_words =
len(words)
print
("the file "
+ filename +
" has about "
+str
(num_words)
+" words."
) 
filenames =
['alice.txt'
,'siddhartha.txt'
,'moby_dick.txt'
,'little_women.txt'
]for filename in filenames:
count_words(filename)

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