blocks|key|1386250|text|join()用于连接所有列表元素。因为只连接两个字符串"%2B“会更有意义：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1386251|strid+=+repr(595)
print+array.array('c',+random.sample(string.ascii_letters,+20+-+len(strid)))
++++.tostring()+%2B+strid|code-block|syntax|javascript|1386252|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|$]]

join() is for concatenating all list elements. For concatenating just two strings "+" would make more sense:

<pre><code>strid = repr(595)
print array.array('c', random.sample(string.ascii_letters, 20 - len(strid)))
 .tostring() + strid
</code></pre>

blocks|key|1171014|text|join接受一个可迭代的东西作为参数。通常是一个列表。在您的例子中，问题是字符串本身是可迭代的，依次给出每个字符。您的代码分解为：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1171015|"wlfgALGbXOahekxSs".join("595")|code-block|syntax|javascript|1171016|它的作用与此相同：|1171017|"wlfgALGbXOahekxSs".join(["5",+"9",+"5"])|1171018|从而产生你的字符串：|1171019|"5wlfgALGbXOahekxSs9wlfgALGbXOahekxSs5"|1171020|作为可迭代的字符串是Python最令人困惑的开始问题之一。|1171021|entityMap^0|0|4|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|Z|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|10|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|11|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|12|8|@]|D|@]|E|$]]|$1|Q|3|R|5|H|7|13|8|@]|D|@]|E|$I|J]]|$1|S|3|T|5|6|7|14|8|@]|D|@]|E|$]]|$1|U|3|-4|5|6|7|15|8|@]|D|@]|E|$]]]|V|$]]

<code>join</code> takes an iterable thing as an argument. Usually it's a list. The problem in your case is that a string is itself iterable, giving out each character in turn. Your code breaks down to this:

<pre><code>"wlfgALGbXOahekxSs".join("595")
</code></pre>

which acts the same as this:

<pre><code>"wlfgALGbXOahekxSs".join(["5", "9", "5"])
</code></pre>

and so produces your string:

<pre><code>"5wlfgALGbXOahekxSs9wlfgALGbXOahekxSs5"
</code></pre>

Strings as iterables is one of the most confusing beginning issues with Python.

blocks|key|1171074|text|要附加一个字符串，只需将其与%2B符号连接起来。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1171075|例如。|1171076|>>>+a+=+"Hello,+"
>>>+b+=+"world"
>>>+str+=+a+%2B+b
>>>+print+str
Hello,+world|code-block|syntax|javascript|1171077|join使用分隔符将字符串连接在一起。分隔符是您放在join前面的内容。例如。|1171078|>>>+"-".join([a,b])
'Hello,+-world'|1171079|Join以字符串列表作为参数。|1171080|entityMap^0|E|1|0|0|0|0|4|Q|4|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|X|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|Y|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|Z|8|@$9|10|A|11|B|C]|$9|12|A|13|B|C]]|D|@]|E|$]]|$1|O|3|P|5|J|7|14|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|15|8|@]|D|@]|E|$]]|$1|S|3|-4|5|6|7|16|8|@]|D|@]|E|$]]]|T|$]]

To append a string, just concatenate it with the <code>+</code> sign.

E.g.

<pre><code>&gt;&gt;&gt; a = "Hello, "
&gt;&gt;&gt; b = "world"
&gt;&gt;&gt; str = a + b
&gt;&gt;&gt; print str
Hello, world
</code></pre>

<code>join</code> connects strings together with a separator. The separator is what you
place right before the <code>join</code>. E.g.

<pre><code>&gt;&gt;&gt; "-".join([a,b])
'Hello, -world'
</code></pre>

Join takes a list of strings as a parameter.

blocks|key|1171142|text|如果你想使用join来简单地连接你的两个字符串，那么你可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1171143|strid+=+repr(595)
print+''.join([array.array('c',+random.sample(string.ascii_letters,+20+-+len(strid)))
++++.tostring(),+strid])|code-block|syntax|javascript|1171144|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 expand a bit more on what others are saying, if you wanted to use join to simply concatenate your two strings, you would do this:

<pre><code>strid = repr(595)
print ''.join([array.array('c', random.sample(string.ascii_letters, 20 - len(strid)))
 .tostring(), strid])
</code></pre>

blocks|key|1386471|text|在提供此作为输入时，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1386472|li+=+['server=mpilgrim',+'uid=sa',+'database=master',+'pwd=secret']
s+=+";".join(li)
print(s)|code-block|syntax|javascript|1386473|Python返回以下内容作为输出：|1386474|'server=mpilgrim;uid=sa;database=master;pwd=secret'|1386475|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]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

On providing this as input ,

<pre><code>li = ['server=mpilgrim', 'uid=sa', 'database=master', 'pwd=secret']
s = ";".join(li)
print(s)
</code></pre>

Python returns this as output :

<pre><code>'server=mpilgrim;uid=sa;database=master;pwd=secret'
</code></pre>

blocks|key|1386526|text|list+=+["my",+"name",+"is",+"kourosh"]+++
"+".join(list)|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1386527|如果这是一个输入，使用JOIN方法，我们可以添加单词之间的距离，还可以将列表转换为字符串。|unstyled|1386528|这是Python输出|1386529|'my+name+is+kourosh'|1386530|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|N|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$B|C]]|$1|K|3|-4|5|F|7|Q|8|@]|9|@]|A|$]]]|L|$]]

<pre><code>list = ["my", "name", "is", "kourosh"] 
" ".join(list)
</code></pre>

If this is an input, using the JOIN method, we can add the distance between the words and also convert the list to the string.

This is Python output 

<pre><code>'my name is kourosh'
</code></pre>

I'm pretty new to Python and am completely confused by <code>.join()</code> which I have read is the preferred method for concatenating strings.

I tried:

<pre><code>strid = repr(595)
print array.array('c', random.sample(string.ascii_letters, 20 - len(strid)))
 .tostring().join(strid)
</code></pre>

and got something like:

<pre><code>5wlfgALGbXOahekxSs9wlfgALGbXOahekxSs5
</code></pre>

Why does it work like this? Shouldn't the <code>595</code> just be automatically appended?

What exactly does the .join() method do?

Python

我是Python的新手，完全被.join()弄糊涂了，我读到它是连接字符串的首选方法。我试过了：strid = repr(595)print array.array('c', random.sample(string.ascii_letters, 20 - len(strid)))    .tostring().joi...

问.join()方法到底做了什么？
EN

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