PYTHON：如何使用 Python 中的 raw_input 将 .txt 文件作为用户的输入，然后按行读取该文件？

我想通过以下方式获取 .txt 文件作为用户的输入raw_input.

输入完成后，我希望访问用户给出的 txt 文件名，并将其内容写入另一个文件（每个文件位于下一行）。

我在如何连接上面的 a 和 b 或如何将原始输入与文件读取链接起来时遇到问题。我需要帮助...代码如下（但它是错误的：S）。

import sys,os,csv

x = raw_input("Enter name of file to be written row wise:")
ui = "x" + txt
for ui in x:
    data = open("ui").readlines()
    outfile = open("myfile.csv","w")
    out = csv.writer(outfile)
for row in data:
    row = row.strip().split(';')
    if row:
        for subrow in row:
            subrow = subrow.strip().split()
            if subrow:
                out.writerow(subrow)
outfile.close()

我收到错误：

无法连接“str”和“list”对象

for row in data: 
    row = row.strip().split(';')

你执行的事实split(';')结果是一行（你应该写：line）根据';'分割总是给出一个非空列表，即使它是一个空行，甚至在被删除之后strip() : ''.split(';') gives ['']。所以你的以下情况if row:是没用的。

这意味着您的代码相当于：

for row in data:
    row = row.strip().split(';')
    for subrow in row:
        subrow = subrow.split()
        if subrow:
            out.writerow(subrow)

然后到：

for row in data:
    for subrow in  row.strip().split(';'):
        subrow = subrow.split()
        if subrow:
            out.writerow(subrow)

.

此外，事实上您使用split() on subrow存在于列表中row.strip().split(';')消除中每个单词之前和之后的所有空格subrow。所以第一个strip() in row.strip().split(';')也是没用的。

那么您的代码相当于：

for row in data:
    for subrow in row.split(';'):
        subrow = subrow.split()
        if subrow:
            out.writerow(subrow)

Now , subrow.split()当子行仅为空白时，可以产生一个空列表，因为split()无参数有其特殊的算法。所以指令if subrow很有用。

.

事实上，在读取这样一个文件的内容之后，您的代码所做的是：

Blackcurrant, Redcurrant   ;  Orange ; Blueberry
    Pear;Chestnut;     Lemon Lime, Grapefruit
Apple;Apricot   ;  Pineapple, Fig; Mulberry, Hedge Apple

记录另一个文件，如下所示：

Blackcurrant
Redcurrant
Orange
Blueberry
Pear
Chestnut
Lemon Lime
Grapefruit
Apple
Apricot
Pineapple
Fig
Mulberry
Hedge
Apple

我更喜欢下面的代码来做到这一点：

filename = raw_input("Enter name of file to be written row wise:") + '.txt'
filepath = 'I:\\' + filename

with open(filepath) as handler,open("myfile.csv","wb") as outfile:
    out = csv.writer(outfile)
    for row in handler:
        gen = ( subrow.split() for subrow in row.split(';') )
        out.writerow([x for x in gen if x])
    del out

.

该代码将始终运行，即使对于内存无法容纳其内容的极其巨大的文件，因为文件的行是一个接一个地读取的。

如果文件不是那么大，可以像您一样继续，使用读取行():

with open(filepath) as handler:
    data = handler.readlines()

with open("myfile.csv","wb") as outfile:
    out = csv.writer(outfile)
    for row in data:
        gen = ( subrow.split() for subrow in row.split(';') )
        out.writerow([x for x in gen if x])
    del out

但没有特别的兴趣继续，所以，你可以这样做for row in handler以及。

.

就我个人而言，我认为使用 writerows() 会更好：

filename = raw_input("Enter name of file to be written row wise:") + '.txt'
filepath = 'I:\\' + filename

with open(filepath) as handler,open("myfile.csv","wb") as outfile:
    out = csv.writer(outfile)
    gen = ( x for row in handler for x in (subrow.split() for subrow in row.split(';')) )
    out.writerows([x for x in gen if])
    del out

.

我通过告诉您使用正则表达式的代码会更加有效来结束这个答案：

import csv, re

regx = re.compile('[ ;\r\n]+')

filename = raw_input("Enter name of file to be written row wise:") + '.txt'
filepath = 'I:\\' + filename

with open(filepath) as handler,open("myfile.txt","w") as outfile:
    outfile.write('\n'.join(x for x in regx.split(handler.read()) if x))

Edit 1

handler = open(filepath)
outfile = open("myfile.txt","wb")
out = csv.writer(outfile)
for row in handler:
    gen = ( subrow.split() for subrow in row.split(';') )
    out.writerow([x for x in gen if x])
del out
outfile.close()
handler.close()

or

import csv, re
regx = re.compile('[ ;\r\n]+')
filename = raw_input("Enter name of file to be written row wise:") + '.txt'
filepath = 'I:\\' + filename

handler = open(filepath)
outfile = open("myfile.txt","w") 
outfile.write('\n'.join(x for x in regx.split(handler.read()) if x))
outfile.close()
handler.close()