Answers for "how to read and write to a text file in python"

python read file to variable

with open('data.txt', 'r') as file:
    data = file.read().replace('\n', '')

how to write to a text file in python

#the way i learned it
#plus explanations

from sys import * #this is for making it more flexible

#so now we gotta open a file to write in

f = open("haha.txt", "w") # the w means WRITING
#now we gotta write something

f.write(str(argv[1])) # the str means change it into a string of letters
#argv[1] means it's the thing you type after the python run thing
#for example: "python run.py helo"

#now we gotta finish it
f.close()

#if you want to see whats in it...

f = open("haha.txt", "r") #r means READING
print(f.read()) # this prints what you wrote

#example input and output

#            python run.py helo
#   helo

reading and writing data in a text file with python

#for reading and writing data in a text file with python
#First you must have a file Open or create a new file have it loaded in memory.
# Open function to open the file "MyFile1.txt" 
# (same directory) in append mode and 
file1 = open("MyFile.txt","a") 

# store its reference in the variable file1 
# and "MyFile2.txt" in D:\Text in file2 
file2 = open(r"D:\Text\MyFile2.txt","w+") 

# Opening and Closing a file "MyFile.txt" 
# for object name file1. 
file1 = open("MyFile.txt","a") 
file1.close() 

# Program to show various ways to read and 
# write data in a file. 
file1 = open("myfile.txt","w") 
L = ["This is Delhi \n","This is Paris \n","This is London \n"] 

# \n is placed to indicate EOL (End of Line) 
file1.write("Hello \n") 
file1.writelines(L) 
file1.close() #to change file access modes 

file1 = open("myfile.txt","r+") 

print "Output of Read function is "
print file1.read() 
print

# seek(n) takes the file handle to the nth 
# bite from the beginning. 
file1.seek(0) 

print "Output of Readline function is "
print file1.readline() 
print

file1.seek(0) 

# To show difference between read and readline 
print "Output of Read(9) function is "
print file1.read(9) 
print

file1.seek(0) 

print "Output of Readline(9) function is "
print file1.readline(9) 

file1.seek(0) 
# readlines function 
print "Output of Readlines function is "
print file1.readlines() 
print
file1.close() 

# Python program to illustrate 
# Append vs write mode 
file1 = open("myfile.txt","w") 
L = ["This is Delhi \n","This is Paris \n","This is London \n"] 
file1.close() 

# Append-adds at last 
file1 = open("myfile.txt","a")#append mode 
file1.write("Today \n") 
file1.close() 

file1 = open("myfile.txt","r") 
print "Output of Readlines after appending"
print file1.readlines() 
print
file1.close() 

# Write-Overwrites 
file1 = open("myfile.txt","w")#write mode 
file1.write("Tomorrow \n") 
file1.close() 

file1 = open("myfile.txt","r") 
print "Output of Readlines after writing"
print file1.readlines() 
print
file1.close() 

Output of Readlines after appending
['This is Delhi \n', 'This is Paris \n', 'This is London \n', 'Today \n']

Output of Readlines after writing
['Tomorrow \n']

read and write file in python

#Write a Python program to create a file of numbers by taking input from the user and then display the content of the file. You can take input of non-zero numbers, with an appropriate prompt, from the user until the user enters a zero to create the file assuming that the numbers are non-zero.  
    f = open ('NumFile.txt','w')
    while True :
        no = int(input("enter a number (0 for exit)"))
        if no == 0 :
            print("you entered zero(0) ....... \n now you are exit  !!!!!!!!!!!")
            break
        else :
            f.write(str(no)+"\n")
    f.close() 
    f1 = open ('NumFile.txt','r')
    print("\ncontent of file :: \n",f1.read())
    f1.close()