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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.
Luck!
Formula
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:
Example f = open("demofile.txt")
print(f.read())If the file is located in a different location, you will have to specify the file path, like this:
Open a file on a different location:
Formula
f = open("D:\\myfiles\welcome.txt")print(f.read())You can also use the with statement when opening a file:
with open("demofile.txt") as f:
print(f.read())Then you do not have to worry about closing your files, the with statement takes care of that.
It is a good practice to always close the file when you are done with it. If you are not using the with statement, you must write a close statement in order to close the file:
Close the file when you are finished with it:
Formula
f = open("demofile.txt")print(f.readline())
f.close()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.
method returns the whole text, but you can also specify how many characters you want to return:Return the 5 first characters of the file: with open("demofile.txt") as f:
print(f.read())
You can return one line by using the readline() method:
Read one line of the file: with open("demofile.txt") as f:
print(f.readline())two times, you can read the two first lines:
Read two lines of the file: with open("demofile.txt") as f:
print(f.readline())
print(f.readline())By looping through the lines of the file, you can read the whole file, line by line:
Loop through the file line by line: with open("demofile.txt") as f: for x in f:
print(x)