Python files

Python read file line by line

with open("file.txt") as file_in:
    lines = []
    for line in file_in:
        lines.append(line)

Source: stackoverflow.com

Python file open modes

r for reading
r+ opens for reading and writing (cannot truncate a file)
w for writing
w+ for writing and reading (can truncate a file)
rb for reading a binary file. The file pointer is placed at the beginning of the file.
rb+ reading or writing a binary file
wb+ writing a binary file
a+ opens for appending
ab+ Opens a file for both appending and reading in binary. The file pointer is at the end of the file if the file exists. The file opens in the append mode.
x open for exclusive creation, failing if the file already exists (Python 3)

Python file open

#there are many modes you can open files in. r means read.
file = open('C:\Users\yourname\files\file.txt','r')
text = file.read()

#you can write a string to it, too!
file = open('C:\Users\yourname\files\file.txt','w')
file.write('This is a typical string')

#don't forget to close it afterwards!
file.close()

Python with file.open

# Reference https://docs.python.org/3/library/functions.html#open

# Method 1
file = open("welcome.txt", "r") # mode can be r(read) w(write) and others 
data = file.read()
file.close()

# Method 2 - automatic close
with open("welcome.txt") as infile:
  data = file.read()

Python file reading

fin = open("NAME.txt", 'r')
body = fin.read().split("\n")
line = fin.readline().strip()

Python files

f = open('filename.txt', 'r') #open for reading (default)
f = open('filename.txt', 'w') #open for writing, truncating the file first
f = open('filename.txt', 'x') #open for exclusive creation, failing if the file already exists
f = open('filename.txt', 'a') #open for writing, appending to the end of the file if it exists

Source: docs.python.org

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