Getting user input [duplicate]

问题

I am running this:

import csv
import sys
reader = csv.reader(open(sys.argv[0], \"rb\"))
for row in reader:
    print row

And I get this in response:

[\'import csv\']
[\'import sys\']
[\'reader = csv.reader(open(sys.argv[0]\', \' \"rb\"))\']
[\'for row in reader:\']
[\'    print row\']
>>>

For the sys.argv[0] I would like it to prompt me to enter a filename.

How do I get it to prompt me to enter a filename?

回答1:

In python 3.x, use input() instead of raw_input()

回答2:

Use the raw_input() function to get input from users (2.x):

print "Enter a file name:",
filename = raw_input()

or just:

filename = raw_input('Enter a file name: ')

or if in Python 3.x:

filename = input('Enter a file name: ')

回答3:

sys.argv[0] is not the first argument but the filename of the python program you are currently executing. I think you want sys.argv[1]

回答4:

To supplement the above answers into something a little more re-usable, I've come up with this, which continues to prompt the user if the input is considered invalid.

try:
    input = raw_input
except NameError:
    pass

def prompt(message, errormessage, isvalid):
    """Prompt for input given a message and return that value after verifying the input.

    Keyword arguments:
    message -- the message to display when asking the user for the value
    errormessage -- the message to display when the value fails validation
    isvalid -- a function that returns True if the value given by the user is valid
    """
    res = None
    while res is None:
        res = input(str(message)+': ')
        if not isvalid(res):
            print str(errormessage)
            res = None
    return res

It can be used like this, with validation functions:

import re
import os.path

api_key = prompt(
        message = "Enter the API key to use for uploading", 
        errormessage= "A valid API key must be provided. This key can be found in your user profile",
        isvalid = lambda v : re.search(r"(([^-])+-){4}[^-]+", v))

filename = prompt(
        message = "Enter the path of the file to upload", 
        errormessage= "The file path you provided does not exist",
        isvalid = lambda v : os.path.isfile(v))

dataset_name = prompt(
        message = "Enter the name of the dataset you want to create", 
        errormessage= "The dataset must be named",
        isvalid = lambda v : len(v) > 0)

回答5:

Use the following simple way to interactively get user data by a prompt as Arguments on what you want.

Version : Python 3.X

name = input('Enter Your Name: ')
print('Hello ', name)

来源：https://stackoverflow.com/questions/3345202/getting-user-input

标签

python

user-input