在Python中逐行读取文件的元素

Question

所以在Ruby中我可以做到以下几点:

testsite_array = Array.new
y=0
File.open('topsites.txt').each do |line|
testsite_array[y] = line
y=y+1
end

如何在Python中做到这一点？

Answer 1

testsite_array = []
with open('topsites.txt') as my_file:
    for line in my_file:
        testsite_array.append(line)

这是可能的,因为Python允许您直接迭代文件.

或者,更简单的方法,使用f.readlines():

with open('topsites.txt') as my_file:
    testsite_array = my_file.readlines()

Answer 2

只需打开文件并使用该readlines()功能:

with open('topsites.txt') as file:
    array = file.readlines()

Answer 3

在python中,您可以使用readlines文件对象的方法.

with open('topsites.txt') as f:
    testsite_array=f.readlines()

或者简单地使用list,这与使用相同,readlines但唯一的区别是我们可以将可选的size参数传递给readlines:

with open('topsites.txt') as f:
    testsite_array=list(f)

帮助file.readlines:

In [46]: file.readlines?
Type:       method_descriptor
String Form:<method 'readlines' of 'file' objects>
Namespace:  Python builtin
Docstring:
readlines([size]) -> list of strings, each a line from the file.

Call readline() repeatedly and return a list of the lines so read.
The optional size argument, if given, is an approximate bound on the
total number of bytes in the lines returned.