blocks|key|166018|text|这取决于您使用的Python版本。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|166019|在Python+2.x中。该表为256个字符的字符串。它可以使用string.maketrans创建|offset|length|style|CODE|166020|>>>+import+string
>>>+tbl+=+string.maketrans('ac',+'dx')
>>>+"abcabc".translate(tbl)
'dbxdbx'|code-block|syntax|javascript|166021|在Python+3.x中，该表是unicode序号到unicode字符的映射。|166022|>>>+"abcabc".translate({ord('a'):+'d',+ord('c'):+'x'})
'dbxdbx'|166023|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/2/library/string.html#string.maketrans^0|0|W|G|W|G|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Z|8|@$D|10|E|11|F|G]]|9|@$D|12|E|13|1|14]]|A|$]]|$1|H|3|I|5|J|7|15|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|16|8|@]|9|@]|A|$]]|$1|O|3|P|5|J|7|17|8|@]|9|@]|A|$K|L]]|$1|Q|3|-4|5|6|7|18|8|@]|9|@]|A|$]]]|R|$S|$5|T|U|V|A|$W|X]]]]

It depends on Python version you are using.

In Python 2.x. The table is 256-characters string. It can be created using <a href="http://docs.python.org/2/library/string.html#string.maketrans"><code>string.maketrans</code></a>:

<pre><code>&gt;&gt;&gt; import string
&gt;&gt;&gt; tbl = string.maketrans('ac', 'dx')
&gt;&gt;&gt; "abcabc".translate(tbl)
'dbxdbx'
</code></pre>

In Python 3.x, the table is mapping of unicode ordinals to unicode characters.

<pre><code>&gt;&gt;&gt; "abcabc".translate({ord('a'): 'd', ord('c'): 'x'})
'dbxdbx'
</code></pre>

blocks|key|167732|text|table必须是256个字符的字符串；str.translate()方法使用此表将字节值(0到255之间的数字)映射到新字符；例如，任何字符'a'+(整数值为97的字节)都将替换为表中的第98个字符。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|167733|您确实希望引用str.translate()+documentation，而不是string.translate()函数；后面的文档并不完整。|167734|您可以使用string.maketrans函数构建一个；您只需将您想要替换的字符指定为替换这些字符的字符即可；对于您的示例，这是：|167735|>>>+import+string
>>>+table+=+string.maketrans('ac',+'cx')
>>>+len(table)
256
>>>+table[97]
'c'
>>>+'abcabc'.translate(table,+'b')
'cxcx'|code-block|syntax|javascript|167736|第二个参数也应该是一个字符串。|167737|您似乎已经阅读了unicode.translate()方法的文档；行为发生了变化，您确实需要传入unicode.translate()的字典。由于Python2中的unicode类型是Python3中的str类型，因此这也是您在Python3中使用str.translate()的方式(其中bytes.translate()与上述行为相匹配)。|167738|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.python.org/2/library/stdtypes.html#str.translate|1|http://docs.python.org/2/library/string.html#string.maketrans^0|0|5|J|F|1Y|3|0|7|F|14|I|7|T|0|0|5|G|5|G|1|0|0|0|8|J|1C|J|2A|7|2T|3|3G|F|41|H|0^^$0|@$1|2|3|4|5|6|7|12|8|@$9|13|A|14|B|C]|$9|15|A|16|B|C]|$9|17|A|18|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|19|8|@$9|1A|A|1B|B|C]|$9|1C|A|1D|B|C]]|D|@$9|1E|A|1F|1|1G]]|E|$]]|$1|H|3|I|5|6|7|1H|8|@$9|1I|A|1J|B|C]]|D|@$9|1K|A|1L|1|1M]]|E|$]]|$1|J|3|K|5|L|7|1N|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|1O|8|@]|D|@]|E|$]]|$1|Q|3|R|5|6|7|1P|8|@$9|1Q|A|1R|B|C]|$9|1S|A|1T|B|C]|$9|1U|A|1V|B|C]|$9|1W|A|1X|B|C]|$9|1Y|A|1Z|B|C]|$9|20|A|21|B|C]]|D|@]|E|$]]|$1|S|3|-4|5|6|7|22|8|@]|D|@]|E|$]]]|T|$U|$5|V|W|X|E|$Y|Z]]|10|$5|V|W|X|E|$Y|11]]]]

<code>table</code> must be a string of 256 characters; the <code>str.translate()</code> method uses this table to map the byte value (a number between 0 and 255) to a new character; e.g. any character <code>'a'</code> (a byte with the integer value 97) is replaced with the 98th character in the table.

You really want to refer to the <a href="http://docs.python.org/2/library/stdtypes.html#str.translate" rel="nofollow noreferrer"><code>str.translate()</code> documentation</a> for all this, not the <code>string.translate()</code> function; the latter documentation is not as complete.

You can build one using <a href="http://docs.python.org/2/library/string.html#string.maketrans" rel="nofollow noreferrer"><code>string.maketrans</code></a> function; you give it just the characters you want to replace with the characters that replace these; for your example, that's:

<pre><code>&gt;&gt;&gt; import string
&gt;&gt;&gt; table = string.maketrans('ac', 'cx')
&gt;&gt;&gt; len(table)
256
&gt;&gt;&gt; table[97]
'c'
&gt;&gt;&gt; 'abcabc'.translate(table, 'b')
'cxcx'
</code></pre>

The second argument is also supposed to be a string.

You appear to have read the documentation for the <code>unicode.translate()</code> method; behaviour changed and you indeed have to pass in a dictionary for <code>unicode.translate()</code>. Since the Python 2 <code>unicode</code> type is the <code>str</code> type in Python 3, that's also how you'd use <code>str.translate()</code> in Python 3 (where <code>bytes.translate()</code> matches the above behaviour).

blocks|key|165029|text|要翻译文本，不使用字典{序号:+char}，而使用字典{char:+char}+(例如{'a'：'X'，'J'：'y'，...}：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|165030|text.translate({ord(k):dictionary[k]+for+k+in+dictionary})|code-block|syntax|javascript|165031|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 translate text, not using a dictionary {ordinal: char}, but a dictionary {char: char} (e.g. {'a': 'X', 'J': 'y', ...}:

<pre><code>text.translate({ord(k):dictionary[k] for k in dictionary})
</code></pre>

Going through the <a href="http://docs.python.org/2/library/string.html#string.translate" rel="noreferrer"><code>string.translate</code></a> function which says:

<blockquote>
 Delete all characters from s that are in deletechars (if present), and then translate the characters using table, which must be a 256-character string giving the translation for each character value, indexed by its ordinal. If table is None, then only the character deletion step is performed.
</blockquote>

<ul>
<li>What does table mean here? Can it be a <code>dict</code> containing the mapping?</li>
<li>What does "must be a 256-character string" mean?</li>
<li>Can the table be made manually or through a custom function instead of <code>string.maketrans</code>?</li>
</ul>

I tried using the function (attempts below) just to see how it worked but wasn't successfully able to use it.

<pre><code>&gt;&gt;&gt; "abcabc".translate("abcabc",{ord("a"): "d", ord("c"): "x"})
Traceback (most recent call last):
 File "&lt;stdin&gt;", line 1, in &lt;module&gt;
ValueError: translation table must be 256 characters long
</code></pre>



<pre><code>&gt;&gt;&gt; "abcabc".translate({ord("a"): ord("d"), ord("c"): ord("x")}, "b")
Traceback (most recent call last):
 File "&lt;stdin&gt;", line 1, in &lt;module&gt;
TypeError: expected a character buffer object
</code></pre>



<pre><code>&gt;&gt;&gt; "abc".translate({"a": "d", "c": "x"}, ["b"])
Traceback (most recent call last):
 File "&lt;stdin&gt;", line 1, in &lt;module&gt;
TypeError: expected a character buffer object
</code></pre>

What am I missing here?

What does "table" in the string.translate function mean?

Python

查看函数，该函数表示：删除deletechars中的所有字符(如果存在)，然后使用表转换字符，表必须是一个256个字符的字符串，给出每个字符值的转换，并按其序号编制索引。如果table为None，则只执行字符删除步骤。表在这里是什么意思？它可以是包含映射的dict吗？“必须是256个字符的字符串”是什么意思？可以手动创...

问string.translate函数中的“表”是什么意思？
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问string.translate函数中的“表”是什么意思？
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