blocks|key|1756264|text|据我所知，最有效的方法是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1756265|import+string

filtered_string+=+filter(lambda+x:+x+in+string.printable,+myStr)|code-block|syntax|javascript|1756266|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|$]]

As far as I know, the most pythonic/efficient method would be:

<pre><code>import string

filtered_string = filter(lambda x: x in string.printable, myStr)
</code></pre>

blocks|key|1756353|text|您可以尝试使用unicodedata.category()函数设置过滤器：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1756354|import+unicodedata
printable+=+{'Lu',+'Ll'}
def+filter_non_printable(str):
++return+''.join(c+for+c+in+str+if+unicodedata.category(c)+in+printable)|code-block|syntax|javascript|1756355|有关可用类别的信息，请参见第175页的Unicode+database+character+properties中的表4-9|1756356|entityMap|0|LINK|mutability|MUTABLE|url|http://www.unicode.org/versions/Unicode9.0.0/ch04.pdf^0|7|M|0|0|J|11|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Y|8|@]|D|@$9|Z|A|10|1|11]]|E|$]]|$1|M|3|-4|5|6|7|12|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|T]]]]

You could try setting up a filter using the <code>unicodedata.category()</code> function:

<pre><code>import unicodedata
printable = {'Lu', 'Ll'}
def filter_non_printable(str):
 return ''.join(c for c in str if unicodedata.category(c) in printable)
</code></pre>

See Table 4-9 on page 175 in the <a href="http://www.unicode.org/versions/Unicode9.0.0/ch04.pdf" rel="noreferrer">Unicode database character properties</a> for the available categories

blocks|key|1541487|text|在Python+3中，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1541488|def+filter_nonprintable(text):
++++import+itertools
++++#+Use+characters+of+control+category
++++nonprintable+=+itertools.chain(range(0x00,0x20),range(0x7f,0xa0))
++++#+Use+translate+to+remove+all+non-printable+characters
++++return+text.translate({character:None+for+character+in+nonprintable})|code-block|syntax|javascript|1541489|有关.translate()与正则表达式&+.replace()的比较，请参阅this+StackOverflow+post+on+removing+punctuation|offset|length|1541490|这些范围可以使用@Ants+Aasma所示的Unicode+character+database+categories通过nonprintable+=+(ord(c)+for+c+in+(chr(i)+for+i+in+range(sys.maxunicode))+if+unicodedata.category(c)=='Cc')生成。|style|CODE|1541491|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/265960/best-way-to-strip-punctuation-from-a-string-in-python|1|http://www.unicode.org/reports/tr44/#General_Category_Values^0|0|0|13|1B|0|0|1P|2X|M|11|1|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@]|9|@$I|11|J|12|1|13]]|A|$]]|$1|K|3|L|5|6|7|14|8|@$I|15|J|16|M|N]]|9|@$I|17|J|18|1|19]]|A|$]]|$1|O|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|P|$Q|$5|R|S|T|A|$U|V]]|W|$5|R|S|T|A|$U|X]]]]

In Python 3,
<pre><code>def filter_nonprintable(text):
 import itertools
 # Use characters of control category
 nonprintable = itertools.chain(range(0x00,0x20),range(0x7f,0xa0))
 # Use translate to remove all non-printable characters
 return text.translate({character:None for character in nonprintable})
</code></pre>
See <a href="https://stackoverflow.com/questions/265960/best-way-to-strip-punctuation-from-a-string-in-python">this StackOverflow post on removing punctuation</a> for how .translate() compares to regex &amp; .replace()
The ranges can be generated via <code>nonprintable = (ord(c) for c in (chr(i) for i in range(sys.maxunicode)) if unicodedata.category(c)=='Cc')</code> using the <a href="http://www.unicode.org/reports/tr44/#General_Category_Values" rel="nofollow noreferrer">Unicode character database categories</a> as shown by @Ants Aasma.

blocks|key|1756524|text|下面的代码将与Unicode输入一起使用，并且速度相当快...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1756525|import+sys

#+build+a+table+mapping+all+non-printable+characters+to+None
NOPRINT_TRANS_TABLE+=+{
++++i:+None+for+i+in+range(0,+sys.maxunicode+%2B+1)+if+not+chr(i).isprintable()
}

def+make_printable(s):
++++"""Replace+non-printable+characters+in+a+string."""

++++#+the+translate+method+on+str+removes+characters
++++#+that+map+to+None+from+the+string
++++return+s.translate(NOPRINT_TRANS_TABLE)


assert+make_printable('Café')+==+'Café'
assert+make_printable('\x00\x11Hello')+==+'Hello'
assert+make_printable('')+==+''|code-block|syntax|javascript|1756526|我自己的测试表明，这种方法比使用str.join遍历字符串并返回结果的函数更快。|offset|length|style|CODE|1756527|entityMap^0|0|0|G|8|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

The following will work with Unicode input and is rather fast...

<pre><code>import sys

# build a table mapping all non-printable characters to None
NOPRINT_TRANS_TABLE = {
 i: None for i in range(0, sys.maxunicode + 1) if not chr(i).isprintable()
}

def make_printable(s):
 """Replace non-printable characters in a string."""

 # the translate method on str removes characters
 # that map to None from the string
 return s.translate(NOPRINT_TRANS_TABLE)


assert make_printable('Café') == 'Café'
assert make_printable('\x00\x11Hello') == 'Hello'
assert make_printable('') == ''
</code></pre>

My own testing suggests this approach is faster than functions that iterate over the string and return a result using <code>str.join</code>.

blocks|key|1756476|text|在python+3中还有另一种选择：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1756477|re.sub(f'[%5E{re.escape(string.printable)}]',+'',+my_string)|code-block|syntax|javascript|1756478|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|$]]

Yet another option in python 3:

<pre><code>re.sub(f'[^{re.escape(string.printable)}]', '', my_string)
</code></pre>

blocks|key|1541377|text|此函数使用列表理解和str.join，因此它在线性时间内运行，而不是O(n%5E2)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1541378|from+curses.ascii+import+isprint

def+printable(input):
++++return+''.join(char+for+char+in+input+if+isprint(char))|code-block|syntax|javascript|1541379|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|$]]

This function uses list comprehensions and str.join, so it runs in linear time instead of O(n^2):

<pre><code>from curses.ascii import isprint

def printable(input):
 return ''.join(char for char in input if isprint(char))
</code></pre>

blocks|key|1756593|text|根据@Ber的回答，我建议只删除Unicode+character+database+categories中定义的控制字符|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1756594|import+unicodedata
def+filter_non_printable(s):
++++return+''.join(c+for+c+in+s+if+not+unicodedata.category(c).startswith('C'))|code-block|syntax|javascript|1756595|entityMap|0|LINK|mutability|MUTABLE|url|http://www.unicode.org/reports/tr44/#General_Category_Values^0|G|11|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Based on @Ber's answer, I suggest removing only control characters as defined in the <a href="http://www.unicode.org/reports/tr44/#General_Category_Values" rel="nofollow noreferrer">Unicode character database categories</a>:
<pre class="lang-py prettyprint-override"><code>import unicodedata
def filter_non_printable(s):
 return ''.join(c for c in s if not unicodedata.category(c).startswith('C'))
</code></pre>

blocks|key|1541301|text|我现在想出的最好的是(感谢上面的python-izers+)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1541302|def+filter_non_printable(str):
++return+''.join([c+for+c+in+str+if+ord(c)+>+31+or+ord(c)+==+9])|code-block|syntax|javascript|1541303|这是我发现处理Unicode字符/字符串的唯一方法|1541304|还有更好的选择吗？|1541305|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

The best I've come up with now is (thanks to the python-izers above) 

<pre><code>def filter_non_printable(str):
 return ''.join([c for c in str if ord(c) &gt; 31 or ord(c) == 9])
</code></pre>

This is the only way I've found out that works with Unicode characters/strings

Any better options?

blocks|key|1541538|text|下面的代码比上面的代码执行得更快。瞧一瞧|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1541539|''.join([x+if+x+in+string.printable+else+''+for+x+in+Str])|code-block|syntax|javascript|1541540|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|$]]

The one below performs faster than the others above. Take a look

<pre><code>''.join([x if x in string.printable else '' for x in Str])
</code></pre>

blocks|key|1756409|text|要删除“空白”，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1756410|import+re
t+=+"""
\n\t&nbsp;\n\t&nbsp;\n\t&nbsp;\n\t&nbsp;\n\t
"""
pat+=+re.compile(r'[\t\n]')
print(pat.sub("",+t))|code-block|syntax|javascript|1756411|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|$]]

To remove 'whitespace',

<pre><code>import re
t = """
\n\t&lt;p&gt;&amp;nbsp;&lt;/p&gt;\n\t&lt;p&gt;&amp;nbsp;&lt;/p&gt;\n\t&lt;p&gt;&amp;nbsp;&lt;/p&gt;\n\t&lt;p&gt;&amp;nbsp;&lt;/p&gt;\n\t&lt;p&gt;
"""
pat = re.compile(r'[\t\n]')
print(pat.sub("", t))
</code></pre>

blocks|key|1541653|text|改编自Ants+Aasma和shawnrad的回答|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1541654|nonprintable+=+set(map(chr,+list(range(0,32))+%2B+list(range(127,160))))
ord_dict+=+{ord(character):None+for+character+in+nonprintable}
def+filter_nonprintable(text):
++++return+text.translate(ord_dict)

#use
str+=+"this+is+my+string"
str+=+filter_nonprintable(str)
print(str)|code-block|syntax|javascript|1541655|在Python+3.7.7上测试|1541656|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/93029/5306011|1|https://stackoverflow.com/a/25829509/5306011^0|3|A|0|E|8|1|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]|$A|Y|B|Z|1|10]]|C|$]]|$1|D|3|E|5|F|7|11|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|12|8|@]|9|@]|C|$]]|$1|K|3|-4|5|6|7|13|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]|S|$5|N|O|P|C|$Q|T]]]]

Adapted from answers by <a href="https://stackoverflow.com/a/93029/5306011">Ants Aasma</a> and <a href="https://stackoverflow.com/a/25829509/5306011">shawnrad</a>:

<pre><code>nonprintable = set(map(chr, list(range(0,32)) + list(range(127,160))))
ord_dict = {ord(character):None for character in nonprintable}
def filter_nonprintable(text):
 return text.translate(ord_dict)

#use
str = "this is my string"
str = filter_nonprintable(str)
print(str)
</code></pre>

tested on Python 3.7.7

blocks|key|1756654|text|在python中从字符串中剥离“不可打印”字符的一种优雅的python解决方案是使用isprintable()字符串方法以及生成器表达式或列表理解，这取决于用例ie。字符串的大小：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1756655|++++''.join(c+for+c+in+my_string+if+c.isprintable())|code-block|syntax|javascript|1756656|如果字符串中的所有字符都是可打印的或者字符串为空，则str.isprintable()返回True，否则返回False。不可打印的字符是那些在Unicode字符数据库中定义为“Other”或“Separator”的字符，但ASCII空格(0x20)除外，它被认为是可打印的。(请注意，此上下文中的可打印字符是在字符串上调用repr()时不应转义的字符。它对写入sys.stdout或sys.stderr的字符串的处理没有影响。)|1756657|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|$]]

An elegant pythonic solution to stripping 'non printable' characters from a string in python is to use the isprintable() string method together with a generator expression or list comprehension depending on the use case ie. size of the string:
<pre><code> ''.join(c for c in my_string if c.isprintable())
</code></pre>
str.isprintable()
Return True if all characters in the string are printable or the string is empty, False otherwise. Nonprintable characters are those characters defined in the Unicode character database as “Other” or “Separator”, excepting the ASCII space (0x20) which is considered printable. (Note that printable characters in this context are those which should not be escaped when repr() is invoked on a string. It has no bearing on the handling of strings written to sys.stdout or sys.stderr.)

I use to run

<pre><code>$s =~ s/[^[:print:]]//g;
</code></pre>

on Perl to get rid of non printable characters. 

In Python there's no POSIX regex classes, and I can't write [:print:] having it mean what I want. I know of no way in Python to detect if a character is printable or not. 

What would you do? 

EDIT: It has to support Unicode characters as well. The string.printable way will happily strip them out of the output. 
curses.ascii.isprint will return false for any unicode character.

Stripping non printable characters from a string in python

数据库

Python

Perl

我过去常常跑步$s =~ s/[^[:print:]]//g;在Perl上删除不可打印的字符。在Python中没有POSIX正则表达式类，我不能写:print:让它意味着我想要的东西。我不知道在Python中有没有办法检测字符是否可打印。你怎么做？编辑:它还必须支持Unicode字符。string.printable方法将很高兴地将它们从输出中剥离出来。对于任何unicode字符，curses.a

问在python中从字符串中剥离不可打印的字符
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