Python file operations open read and write files append text content instances

1.open must remember to call the close() method of the file object after opening the file with open. For example, you can use the try/finally statement to make sure you close the file at the end.

file_object = open('thefile.txt')
try:
 all_the_text = file_object.read( )
finally:
 file_object.close( )

Note: you cannot put the open statement in the try block, because the file object file_object cannot execute the close() method when an exception occurs when you open the file.

2. Read file read text file input = open('data', 'r')

# The first 2 The default value is r
input = open('data')

Read the base 2 file input = open('data', 'rb')

Read everything file_object = open(' thefile.txt ')

try:
 all_the_text = file_object.read( )
finally:
 file_object.close( )

Read fixed byte file_object = open('abinfile', 'rb')

try:
 while True:
 chunk = file_object.read(100)
 if not chunk:
 break
 do_something_with(chunk)
finally:
 file_object.close( )

Read each line list_of_all_the_lines = file_object.readlines ()

If the file is a text file, you can also directly traverse the file object to get each line:

for line in file_object:
 process line

3. Write a file write a text file output = open(' data.txt ', 'w')

Write the base 2 file output = open(' data.txt ', 'wb')

Append write file output = open(' data.txt ', 'a')

output .write("\n There are good people ")

output .close( )

Write data file_object = open(' thefile.txt ', 'w')

file_object.write(all_the_text)
file_object.close( )