blocks|key|1357296|text|为了提供另一种解决方案：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1357297|import+linecache
linecache.getline('Sample.txt',+Number_of_Line)|code-block|syntax|javascript|1357298|我希望这是快速而简单的:)|1357299|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

For the sake of offering another solution:

<pre><code>import linecache
linecache.getline('Sample.txt', Number_of_Line)
</code></pre>

I hope this is quick and easy :)

blocks|key|1357338|text|读取文件的速度令人难以置信。读取100MB的文件只需不到0.1秒(请参阅我的文章Reading+and+Writing+Files+with+Python)。因此，您应该完整地阅读它，然后使用单行代码。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1357339|这里的大多数答案并不是错误的，而是糟糕的风格。打开文件应该始终使用with，因为它会确保文件再次关闭。|style|CODE|1357340|所以你应该这样做：|1357341|with+open("path/to/file.txt")+as+f:
++++lines+=+f.readlines()
print(lines[26])++#+or+whatever+you+want+to+do+with+this+line
print(lines[30])++#+or+whatever+you+want+to+do+with+this+line|code-block|syntax|javascript|1357342|巨大的文件|1357343|如果您碰巧有一个巨大的文件，并且需要考虑内存消耗，您可以逐行处理它：|1357344|with+open("path/to/file.txt")+as+f:
++++for+i,+line+in+enumerate(f):
++++++++pass++#+process+line+i|1357345|entityMap|0|LINK|mutability|MUTABLE|url|https://martin-thoma.com/reading-and-writing-files-with-python/|1|https://docs.python.org/3/reference/compound_stmts.html#with^0|14|11|0|0|X|4|X|4|1|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@$A|15|B|16|1|17]]|C|$]]|$1|D|3|E|5|6|7|18|8|@$A|19|B|1A|F|G]]|9|@$A|1B|B|1C|1|1D]]|C|$]]|$1|H|3|I|5|6|7|1E|8|@]|9|@]|C|$]]|$1|J|3|K|5|L|7|1F|8|@]|9|@]|C|$M|N]]|$1|O|3|P|5|6|7|1G|8|@]|9|@]|C|$]]|$1|Q|3|R|5|6|7|1H|8|@]|9|@]|C|$]]|$1|S|3|T|5|L|7|1I|8|@]|9|@]|C|$M|N]]|$1|U|3|-4|5|6|7|1J|8|@]|9|@]|C|$]]]|V|$W|$5|X|Y|Z|C|$10|11]]|12|$5|X|Y|Z|C|$10|13]]]]

Reading files is incredible fast. Reading a 100MB file takes less than 0.1 seconds (see my article <a href="https://martin-thoma.com/reading-and-writing-files-with-python/" rel="noreferrer">Reading and Writing Files with Python</a>). Hence you should read it completely and then work with the single lines.

What most answer here do is not wrong, but bad style. Opening files should always be done with <a href="https://docs.python.org/3/reference/compound_stmts.html#with" rel="noreferrer"><code>with</code></a> as it makes sure that the file is closed again.

So you should do it like this:

<pre><code>with open("path/to/file.txt") as f:
 lines = f.readlines()
print(lines[26]) # or whatever you want to do with this line
print(lines[30]) # or whatever you want to do with this line
</code></pre>

<h2>Huge files</h2>

If you happen to have a huge file and memory consumption is a concern, you can process it line by line:

<pre><code>with open("path/to/file.txt") as f:
 for i, line in enumerate(f):
 pass # process line i
</code></pre>

blocks|key|1142538|text|其中一些很可爱，但可以更简单地完成：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1142539|start+=+0+#+some+starting+index
end+=+5000+#+some+ending+index
filename+=+'test.txt'+#+some+file+we+want+to+use

with+open(filename)+as+fh:
++++data+=+fin.readlines()[start:end]

print(data)|code-block|syntax|javascript|1142540|这将使用简单的列表切片，它加载整个文件，但大多数系统将适当地最小化内存使用，它比上面给出的大多数方法更快，并且适用于我的10G%2B数据文件。祝好运!|1142541|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Some of these are lovely, but it can be done much more simply:

<pre><code>start = 0 # some starting index
end = 5000 # some ending index
filename = 'test.txt' # some file we want to use

with open(filename) as fh:
 data = fin.readlines()[start:end]

print(data)
</code></pre>

That will use simply list slicing, it loads the whole file, but most systems will minimise memory usage appropriately, it's faster than most of the methods given above, and works on my 10G+ data files. Good luck!

blocks|key|1357051|text|您可以执行一个seek()调用，将您的读取头定位到文件中的指定字节。除非您确切地知道在要读取行之前在文件中写入了多少字节(字符)，否则这对您没有任何帮助。也许您的文件是严格格式化的(每行都是X个字节？)或者，如果你真的想要提高速度，你可以自己计算字符数(记住包括一些看不见的字符，比如换行符)。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1357052|否则，您必须按照这里提出的众多解决方案中的一种，在您想要的行之前阅读每一行。|1357053|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/tutorial/inputoutput.html^0|7|6|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@$A|O|B|P|1|Q]]|C|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@]|C|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|C|$]]]|G|$H|$5|I|J|K|C|$L|M]]]]

You can do a <a href="http://docs.python.org/tutorial/inputoutput.html" rel="noreferrer">seek()</a> call which positions your read head to a specified byte within the file. This won't help you unless you know exactly how many bytes (characters) are written in the file before the line you want to read. Perhaps your file is strictly formatted (each line is X number of bytes?) or, you could count the number of characters yourself (remember to include invisible characters like line breaks) if you really want the speed boost. 

Otherwise, you do have to read every line prior to the line you desire, as per one of the many solutions already proposed here.

blocks|key|1142050|text|def+getitems(iterable,+items):
++items+=+list(items)+#+get+a+list+from+any+iterable+and+make+our+own+copy
++++++++++++++++++++++#+since+we+modify+it
++if+items:
++++items.sort()
++++for+n,+v+in+enumerate(iterable):
++++++if+n+==+items[0]:
++++++++yield+v
++++++++items.pop(0)
++++++++if+not+items:
++++++++++break

print+list(getitems(open("/usr/share/dict/words"),+[25,+29]))
#+['Abelson\n',+'Abernathy\n']
#+note+that+index+25+is+the+26th+item|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1142051|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>def getitems(iterable, items):
 items = list(items) # get a list from any iterable and make our own copy
 # since we modify it
 if items:
 items.sort()
 for n, v in enumerate(iterable):
 if n == items[0]:
 yield v
 items.pop(0)
 if not items:
 break

print list(getitems(open("/usr/share/dict/words"), [25, 29]))
# ['Abelson\n', 'Abernathy\n']
# note that index 25 is the 26th item
</code></pre>

blocks|key|1357886|text|with+open("test.txt",+"r")+as+fp:
+++lines+=+fp.readlines()
print(lines[3])|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1357887|test.txt是文件名|unstyled|1357888|打印test.txt中的第四行|1357889|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre class="lang-py prettyprint-override"><code>with open(&quot;test.txt&quot;, &quot;r&quot;) as fp:
 lines = fp.readlines()
print(lines[3])
</code></pre>
test.txt is filename 
prints line number four in test.txt

blocks|key|1356935|text|这样如何：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1356936|>>>+with+open('a',+'r')+as+fin:+lines+=+fin.readlines()
>>>+for+i,+line+in+enumerate(lines):
++++++if+i+>+30:+break
++++++if+i+==+26:+dox()
++++++if+i+==+30:+doy()|code-block|syntax|javascript|1356937|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

How about this:

<pre><code>&gt;&gt;&gt; with open('a', 'r') as fin: lines = fin.readlines()
&gt;&gt;&gt; for i, line in enumerate(lines):
 if i &gt; 30: break
 if i == 26: dox()
 if i == 30: doy()
</code></pre>

blocks|key|1356986|text|如果您不介意导入，那么fileinput将执行您需要的操作(即您可以读取当前行的行号)。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1356987|entityMap|0|LINK|mutability|MUTABLE|url|http://pydoc.org/2.5.1/fileinput.html^0|B|9|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

If you don't mind importing then <a href="http://pydoc.org/2.5.1/fileinput.html" rel="nofollow noreferrer">fileinput</a> does exactly what you need (this is you can read the line number of the current line)

blocks|key|1142141|text|我更喜欢这种方法，因为它更通用，也就是说，你可以在文件上，在f.readlines()的结果上，在StringIO对象上使用它，无论是什么：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1142142|def+read_specific_lines(file,+lines_to_read):
+++"""file+is+any+iterable;+lines_to_read+is+an+iterable+containing+int+values"""
+++lines+=+set(lines_to_read)
+++last+=+max(lines)
+++for+n,+line+in+enumerate(file):
++++++if+n+%2B+1+in+lines:
++++++++++yield+line
++++++if+n+%2B+1+>+last:
++++++++++return

>>>+with+open(r'c:\temp\words.txt')+as+f:
++++++++[s+for+s+in+read_specific_lines(f,+[1,+2,+3,+1000])]
['A\n',+'a\n',+'aa\n',+'accordant\n']|code-block|syntax|javascript|1142143|entityMap^0|U|D|1D|8|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

I prefer this approach because it's more general-purpose, i.e. you can use it on a file, on the result of <code>f.readlines()</code>, on a <code>StringIO</code> object, whatever:

<pre><code>def read_specific_lines(file, lines_to_read):
 """file is any iterable; lines_to_read is an iterable containing int values"""
 lines = set(lines_to_read)
 last = max(lines)
 for n, line in enumerate(file):
 if n + 1 in lines:
 yield line
 if n + 1 &gt; last:
 return

&gt;&gt;&gt; with open(r'c:\temp\words.txt') as f:
 [s for s in read_specific_lines(f, [1, 2, 3, 1000])]
['A\n', 'a\n', 'aa\n', 'accordant\n']
</code></pre>

blocks|key|1357271|text|这是我的2美分，值得一提。)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1357272|def+indexLines(filename,+lines=[2,4,6,8,10,12,3,5,7,1]):
++++fp+++=+open(filename,+"r")
++++src++=+fp.readlines()
++++data+=+[(index,+line)+for+index,+line+in+enumerate(src)+if+index+in+lines]
++++fp.close()
++++return+data


#+Usage+below
filename+=+"C:\\Your\\Path\\And\\Filename.txt"
for+line+in+indexLines(filename):+#+using+default+list,+specify+your+own+list+of+lines+otherwise
++++print+"Line:+%25s\nData:+%25s\n"+%25+(line[0],+line[1])|code-block|syntax|javascript|1357273|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here's my little 2 cents, for what it's worth ;)

<pre><code>def indexLines(filename, lines=[2,4,6,8,10,12,3,5,7,1]):
 fp = open(filename, "r")
 src = fp.readlines()
 data = [(index, line) for index, line in enumerate(src) if index in lines]
 fp.close()
 return data


# Usage below
filename = "C:\\Your\\Path\\And\\Filename.txt"
for line in indexLines(filename): # using default list, specify your own list of lines otherwise
 print "Line: %s\nData: %s\n" % (line[0], line[1])
</code></pre>

blocks|key|1142448|text|对Alok+Singhal的答案进行了更好和更小的更改|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1142449|fp+=+open("file")
for+i,+line+in+enumerate(fp,1):
++++if+i+==+26:
++++++++#+26th+line
++++elif+i+==+30:
++++++++#+30th+line
++++elif+i+>+30:
++++++++break
fp.close()|code-block|syntax|javascript|1142450|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

A better and minor change for Alok Singhal's answer

<pre><code>fp = open("file")
for i, line in enumerate(fp,1):
 if i == 26:
 # 26th line
 elif i == 30:
 # 30th line
 elif i &gt; 30:
 break
fp.close()
</code></pre>

blocks|key|1142482|text|您可以使用前面提到的语法非常简单地做到这一点，但这是目前为止最简单的方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1142483|inputFile+=+open("lineNumbers.txt",+"r")
lines+=+inputFile.readlines()
print+(lines[0])
print+(lines[2])|code-block|syntax|javascript|1142484|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can do this very simply with this syntax that someone already mentioned, but it's by far the easiest way to do it:

<pre><code>inputFile = open("lineNumbers.txt", "r")
lines = inputFile.readlines()
print (lines[0])
print (lines[2])
</code></pre>

blocks|key|1356906|text|文件对象有一个.readlines()方法，它为您提供文件内容的列表，每个列表项占一行。在此之后，您可以只使用普通的列表切片技术。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1356907|http://docs.python.org/library/stdtypes.html#file.readlines|offset|length|1356908|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|1N|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@$D|O|E|P|1|Q]]|A|$]]|$1|F|3|-4|5|6|7|R|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|C]]]]

File objects have a .readlines() method which will give you a list of the contents of the file, one line per list item. After that, you can just use normal list slicing techniques.

<a href="http://docs.python.org/library/stdtypes.html#file.readlines" rel="nofollow noreferrer">http://docs.python.org/library/stdtypes.html#file.readlines</a>

blocks|key|1357211|text|@OP，您可以使用enumerate|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1357212|for+n,line+in+enumerate(open("file")):
++++if+n%2B1+in+[26,30]:+#+or+n+in+[25,29]+
+++++++print+line.rstrip()|code-block|syntax|javascript|1357213|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

@OP, you can use enumerate

<pre><code>for n,line in enumerate(open("file")):
 if n+1 in [26,30]: # or n in [25,29] 
 print line.rstrip()
</code></pre>

blocks|key|1142424|text|file+=+'/path/to/file_to_be_read.txt'
with+open(file)+as+f:
++++print+f.readlines()[26]
++++print+f.readlines()[30]|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1142425|使用with语句，这将打开文件，打印第26行和第30行，然后关闭文件。很简单！|unstyled|1142426|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>file = '/path/to/file_to_be_read.txt'
with open(file) as f:
 print f.readlines()[26]
 print f.readlines()[30]
</code></pre>

Using the with statement, this opens the file, prints lines 26 and 30, then closes the file. Simple!

blocks|key|1357634|text|为了打印line#+3，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1357635|line_number+=+3

with+open(filename,"r")+as+file:
current_line+=+1
for+line+in+file:
++++if+current_line+==+line_number:
++++++++print(file.readline())
++++++++break
++++current_line+%2B=+1|code-block|syntax|javascript|1357636|原作者:弗兰克·霍夫曼|1357637|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

To print line# 3, 

<pre><code>line_number = 3

with open(filename,"r") as file:
current_line = 1
for line in file:
 if current_line == line_number:
 print(file.readline())
 break
 current_line += 1
</code></pre>

Original author: Frank Hofmann

blocks|key|1142715|text|相当快，而且切中要害。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1142716|打印文本文件中的某些行。创建一个"+lines2print“列表，然后在枚举在lines2print列表中时打印。若要删除多余的'\n‘，请使用line.strip()或line.strip('\n')。我只是喜欢“列表理解”，并在可能的情况下尝试使用。我喜欢使用"with“方法来读取文本文件，以防止文件因任何原因而处于打开状态。|1142717|lines2print+=+[26,30]+#+can+be+a+big+list+and+order+doesn't+matter.

with+open("filepath",+'r')+as+fp:
++++[print(x.strip())+for+ei,x+in+enumerate(fp)+if+ei+in+lines2print]|code-block|syntax|javascript|1142718|或者，如果列表很小，只需将列表作为列表键入到理解中即可。|1142719|with+open("filepath",+'r')+as+fp:
++++[print(x.strip())+for+ei,x+in+enumerate(fp)+if+ei+in+[26,30]]|1142720|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

<h2>Fairly quick and to the point.</h2>

To print certain lines in a text file. Create a "lines2print" list and then
just print when the enumeration is "in" the lines2print list.
To get rid of extra '\n' use line.strip() or line.strip('\n').
I just like "list comprehension" and try to use when I can.
I like the "with" method to read text files in order to prevent
leaving a file open for any reason.

<pre><code>lines2print = [26,30] # can be a big list and order doesn't matter.

with open("filepath", 'r') as fp:
 [print(x.strip()) for ei,x in enumerate(fp) if ei in lines2print]
</code></pre>

or if list is small just type in list as a list into the comprehension.

<pre><code>with open("filepath", 'r') as fp:
 [print(x.strip()) for ei,x in enumerate(fp) if ei in [26,30]]
</code></pre>

blocks|key|1357600|text|打印所需的行。要在所需行的上方/下方打印行。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1357601|def+dline(file,no,add_sub=0):
++++tf=open(file)
++++for+sno,line+in+enumerate(tf):
++++++++if+sno==no-1%2Badd_sub:
+++++++++print(line)
++++tf.close()|code-block|syntax|javascript|1357602|执行->dline(“D：\dummy.txt”，6)i.e.dline(“文件路径”，line_number，如果想要搜索到的行的上一行给1表示下一行，这是一个可选的默认值，取0)|1357603|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

To print desired line.
To print line above/below required line.

<pre><code>def dline(file,no,add_sub=0):
 tf=open(file)
 for sno,line in enumerate(tf):
 if sno==no-1+add_sub:
 print(line)
 tf.close()
</code></pre>

execute---->dline("D:\dummy.txt",6) i.e dline("file path", line_number, if you want upper line of the searched line give 1 for lower -1 this is optional default value will be taken 0)

blocks|key|1357812|text|如果您想读取特定的行，比如在某个阈值行之后开始的行，那么您可以使用以下代码，file++=+open("files.txt","r")+lines+=+file.readlines()+##+convert+to+list+of+lines+datas++=+lines[11:]++##+raed+the+specific+lines|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1357813|entityMap^0|12|3M|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

If you want to read specific lines, such as line starting after some threshold line then you can use the following codes,
<code>file = open("files.txt","r")
lines = file.readlines() ## convert to list of lines
datas = lines[11:] ## raed the specific lines</code>

blocks|key|1142075|text|f+=+open(filename,+'r')
totalLines+=+len(f.readlines())
f.close()
f+=+open(filename,+'r')

lineno+=+1
while+lineno+<+totalLines:
++++line+=+f.readline()

++++if+lineno+==+26:
++++++++doLine26Commmand(line)

++++elif+lineno+==+30:
++++++++doLine30Commmand(line)

++++lineno+%2B=+1
f.close()|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1142076|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>f = open(filename, 'r')
totalLines = len(f.readlines())
f.close()
f = open(filename, 'r')

lineno = 1
while lineno &lt; totalLines:
 line = f.readline()

 if lineno == 26:
 doLine26Commmand(line)

 elif lineno == 30:
 doLine30Commmand(line)

 lineno += 1
f.close()
</code></pre>

blocks|key|1142375|text|我想这会行得通|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1142376|+open_file1+=+open("E:\\test.txt",'r')
+read_it1+=+open_file1.read()
+myline1+=+[]
+for+line1+in+read_it1.splitlines():
+myline1.append(line1)
+print+myline1[0]|code-block|syntax|javascript|1142377|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I think this would work

<pre><code> open_file1 = open("E:\\test.txt",'r')
 read_it1 = open_file1.read()
 myline1 = []
 for line1 in read_it1.splitlines():
 myline1.append(line1)
 print myline1[0]
</code></pre>

blocks|key|1142825|text|从特定行读取：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1142826|n+=+4+++#+for+reading+from+5th+line
with+open("write.txt",'r')+as+t:
+++++for+i,line+in+enumerate(t):
+++++++++if+i+>=+n:+++++++++++++#+i+==+n-1+for+nth+line
++++++++++++print(line)|code-block|syntax|javascript|1142827|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Reading from specific line:
<pre><code>n = 4 # for reading from 5th line
with open(&quot;write.txt&quot;,'r') as t:
 for i,line in enumerate(t):
 if i &gt;= n: # i == n-1 for nth line
 print(line)
</code></pre>

I'm using a <code>for</code> loop to read a file, but I only want to read specific lines, say line <code>#26</code> and <code>#30</code>. Is there any built-in feature to achieve this?

How to read specific lines from a file (by line number)?

我使用for循环来读取文件，但我只想读取特定的行，比如行#26和#30。有没有什么内置的特性来实现这一点呢？

问如何从文件中读取特定行(按行号)？
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回答 22

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问如何从文件中读取特定行(按行号)？
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