Python File Open
Open a File on the Server
Assume we have the following file, located in the same folder as Python:
demofile.txt
Hello! Welcome to demofile.txt
This file is for testing purposes.
Good
Luck!
To open the file, use the built-in open() function.
The open() function returns a file object, which has a
read() method for reading the content of the file:
Read Only Parts of the File
By default the read() method returns the whole text, but you can also specify how many characters you want to return:
Example
Return the 5 first characters of the file:
f = open("demofile.txt", "r")
print(f.read(5))
Run example »
Read Lines
You can return one line by using the readline() method:
By calling readline() two times, you can read the
two first lines:
Example
Read two lines of the file:
f = open("demofile.txt", "r")
print(f.readline())
print(f.readline())
Run example »
By looping through the lines of the file, you can read the whole file, line by line:
Example
Loop through the file line by line:
f = open("demofile.txt", "r")
for x in f:
print(x)
Run example »
Close Files
It is a good practice to always close the file when you are done with it.
Example
Close the file when you are finish with it:
f = open("demofile.txt", "r")
print(f.readline())
f.close()
Run example »
Note: You should always close your files, in some cases, due to buffering, changes made to a file may not show until you close the file.
