如何使用python阅读和打印整个.txt文件？

Question

I am totally new to python, and I am supposed to write a program that can read a whole .txt file and print it. The file is an article in my first language(Norwegian), and long. I have three versions that should do the same thing, but all get error. I have tried in bot PyCharm and eclipse with PyDev installed, and i get the same errors on both...

from sys import argv

import pip._vendor.distlib.compat

script, dev = argv

txt = open(dev)

print("Here's your file %r:" % dev)
print(txt.read())


print("Type the filename again:")h
file_again = pip._vendor.distlib.compat.raw_input("> ")

txt_again = open(file_again)

print(txt_again.read())

But this gets the errors:

Traceback (most recent call last):
File "/Users/vebjornbergaplass/Documents/Python eclipse/oblig1/src/1A/1A.py", line 5, in <module>
script, dev = argv
ValueError: not enough values to unpack (expected 2, got 1)

Again, i am new to python, and i searched around, but didn't find a solution.

My next attempt was this:

# -*- coding: utf-8 -*-

import sys, traceback

fr = open('dev.txt', 'r')
text = fr.read()
print(text)

But this gets these errors:

Traceback (most recent call last):
    File "/Users/vebjornbergaplass/Documents/Python eclipse/oblig1/src/1A/v2.py", line 6, in <module>
        text = fr.read()

  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/encodings/ascii.py", line 26, in decode
    return codecs.ascii_decode(input, self.errors)[0]

UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 26: ordinal not in range(128)

I do not understand why i doesn't work.

My third attempt looks like this:

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import argparse
parser = argparse.ArgumentParser()

parser.add_argument("dev.txt", help="dev.txt")
args = parser.parse_args()
if args.filename:
    with open('dev.txt') as f:
        for line in f:
            name, _ = line.strip().split('\t')
            print(name)

And this gets the errors:

usage: v3.py [-h] dev.txt
v3.py: error: the following arguments are required: dev.txt

Any help to why these doesnt work is welcome. Thank you in advance :D

Answer 1

file = open("File.txt", "r")
a = str(file.read())

print(a)

Is this what you were looking for?

Answer 2

For the 2nd approach is the simplest, I'll stick to it.

You stated the contents of dev.txt to be Norwegian, that means, it will include non-ascii characters like Æ,Ø,Å etc. The python interpreter is trying to tell you this:

UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 26: ordinal not in range(128) It cannot interpret the byte 0xC3 = 195 (decimal) as an ascii character, which is limited to a range of 128 different characters.

I'll assume you're using UTF-8 as encoding but if not, change the parameter in line 2.

# -*- coding: utf-8 -*-

fr = open('dev.txt', 'r', encoding='utf-8')
text = fr.read()
print(text)

If you do not know your encoding, you can find it out via your editor or use python to guess it .

Your terminal could also cause the error when it's not configured to print Unicode Characters or map them correctly. You might want to take a look at this question and its answers.

---

After operating a file, it is recommended to close it. You can either do that manually via fr.close() or make python do it automatically:

with open('dev.txt', 'r', encoding='utf-8') as fr:
    # automatically closes fr when leaving this code-block

Answer 3

For example:

open ("fileA.txt", "r") as fileA:
    for line in fileA:
        print(line);

Answer 4

This is a possible solution:

f = open("textfile.txt", "r")
lines = f.readlines()
for line in lines:
    print(line)
f.close()

Save it as for example myscript.py and execute it:

python /path/to/myscript.py