blocks|key|5410|text|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5411|+...那么只要$info被赋值为false以外的值，这段代码就会执行吗？|blockquote|5412|5413|5414|是的，确实如此。即使表达式中有一个赋值运算符，表达式本身仍然代表一个值。在这种情况下，整个表达式的结果等于对$info的赋值。换句话说:表达式与$info相同，或者表达式已赋值给$info+-最后一个变体可能是最好的描述。|offset|length|style|CODE|5415|所以现在只要$info等于true，while内部的代码块就会被执行。|5416|请记住，这种比较是一个loose+comparison。因此，不仅是false，还有NULL或空数组都会停止内部代码块的执行。|5417|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/manual/en/types.comparisons.php#types.comparisions-loose^0|0|0|0|0|1I|5|20|5|2H|5|0|6|5|D|4|I|5|0|Y|5|16|4|B|G|0|0^^$0|@$1|2|3|-4|4|5|6|X|7|@]|8|@]|9|$]]|$1|A|3|B|4|C|6|Y|7|@]|8|@]|9|$]]|$1|D|3|-4|4|5|6|Z|7|@]|8|@]|9|$]]|$1|E|3|-4|4|5|6|10|7|@]|8|@]|9|$]]|$1|F|3|G|4|5|6|11|7|@$H|12|I|13|J|K]|$H|14|I|15|J|K]|$H|16|I|17|J|K]]|8|@]|9|$]]|$1|L|3|M|4|5|6|18|7|@$H|19|I|1A|J|K]|$H|1B|I|1C|J|K]|$H|1D|I|1E|J|K]]|8|@]|9|$]]|$1|N|3|O|4|5|6|1F|7|@$H|1G|I|1H|J|K]|$H|1I|I|1J|J|K]]|8|@$H|1K|I|1L|1|1M]]|9|$]]|$1|P|3|-4|4|5|6|1N|7|@]|8|@]|9|$]]]|Q|$R|$4|S|T|U|9|$V|W]]]]

<blockquote>
 [... S]o as long as $info gets assigned a value other than false, this code will execute?
</blockquote>

Quite, yes. Even there is an assignment operator within that expression, the expression itself still stands for a value. In this case the result of the whole expression is equal to the assignment to <code>$info</code>. In other words: The expression is the same as <code>$info</code> or the expression has been assigned to <code>$info</code> - the last variant is perhaps the best description.

So now whenever <code>$info</code> equals to <code>true</code>, the code block inside <code>while</code> will be executed.

Keep in mind that the comparison is a <a href="http://php.net/manual/en/types.comparisons.php#types.comparisions-loose">loose comparison</a>. So not only <code>false</code> but as well <code>NULL</code> or an empty array will stop the execution of the inner code-block.

blocks|key|3161356|text|对于每个记录，$info将使用当前行进行填充，直到它到达结果集的末尾，此时它将被设置为false+(这将停止while循环)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3161357|entityMap^0|7|5|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|$]]

For each record <code>$info</code> will be populated with the current row, until it reaches the end of the result set when it will be set to false (which should stop the while loop).

blocks|key|5460|text|hakre的回答很棒。据说是，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5461|while+($info=mysql_fetch_array($data_jurisdiction))|code-block|syntax|javascript|5462|将以与此相同的方式执行|5463|while+(mysql_fetch_array($data_jurisdiction)==true)|5464|或者甚至是这个|5465|$info+=+mysql_fetch_array($data_jurisdiction);
if($info==true)|5466|因此请记住，如果mysql_fetch_array($data_jurisdiction)返回任何可以计算为false的内容，则赋值将不起作用。其中一些值是(我知道我会忘记一些：|5467|5468|unordered-list-item|5469|"0"|5470|false|5471|"false"|5472|NULL|5473|""|5474|array()+(不完全确定这一点)|5475|5476|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|19|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|1A|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|1B|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|1C|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|1D|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1E|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|1F|8|@]|9|@]|A|$]]|$1|R|3|-4|5|S|7|1G|8|@]|9|@]|A|$]]|$1|T|3|U|5|S|7|1H|8|@]|9|@]|A|$]]|$1|V|3|W|5|S|7|1I|8|@]|9|@]|A|$]]|$1|X|3|Y|5|S|7|1J|8|@]|9|@]|A|$]]|$1|Z|3|10|5|S|7|1K|8|@]|9|@]|A|$]]|$1|11|3|12|5|S|7|1L|8|@]|9|@]|A|$]]|$1|13|3|14|5|S|7|1M|8|@]|9|@]|A|$]]|$1|15|3|-4|5|6|7|1N|8|@]|9|@]|A|$]]|$1|16|3|-4|5|6|7|1O|8|@]|9|@]|A|$]]]|17|$]]

great answer from hakre. what is said is that 

<pre><code>while ($info=mysql_fetch_array($data_jurisdiction))
</code></pre>

will execute in the same way as this

<pre><code>while (mysql_fetch_array($data_jurisdiction)==true)
</code></pre>

or even this

<pre><code>$info = mysql_fetch_array($data_jurisdiction);
if($info==true)
</code></pre>

so keep in mind that if mysql_fetch_array($data_jurisdiction) returns anything that can be evaluated to false, the assignment won't work. some of those values are (and I know I will forget a few:

<ul>
<li>0</li>
<li>"0"</li>
<li>false</li>
<li>"false"</li>
<li>NULL</li>
<li>""</li>
<li>array() (not fully sure about this one)</li>
</ul>

blocks|key|3446201|text|只要为$info分配了一个非false的值，此代码就会执行吗？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3446202|是。|offset|length|style|BOLD|3446203|entityMap^0|0|0|2|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

as long as $info gets assigned a value other than false, this code will execute?

Yes.

blocks|key|5222|text|如果$info为false，它会循环并停止|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|5223|mysql_fetch_array();逐行清除，因此每次都有新的结果|5224|entityMap^0|2|5|0|0|K|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|P|8|@]|D|@]|E|$]]]|I|$]]

it does loop and stops if <code>$info</code> is false

<code>mysql_fetch_array();</code> clears row by row so there is new result alltimes

blocks|key|3446288|text|只要while表达式的计算结果为true，while循环就会重复执行嵌套语句。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3446289|示例$info+=+mysql_fetch_object($data_jurisdiction)中的表达式在类型杂耍之后检查$info，即来自mysql_fetch_object()的赋值是否等于true。|BOLD|3446290|这里有两点很重要：|3446291|3446292|mysql_fetch_object()返回结果集的下一行，直到到达数据集的末尾，它返回false。请查看不等于0的变量的method+documentation+here.|ordered-list-item|3446293|All赋值，或在类型调整后null求值为true。|3446294|3446295|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/manual/en/function.mysql-fetch-object.php^0|G|4|0|2|1A|1Q|5|1Z|K|1I|4|0|0|0|0|K|1P|P|0|0|D|4|0|0^^$0|@$1|2|3|4|5|6|7|Z|8|@$9|10|A|11|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|12|8|@$9|13|A|14|B|C]|$9|15|A|16|B|C]|$9|17|A|18|B|C]|$9|19|A|1A|B|H]]|D|@]|E|$]]|$1|I|3|J|5|6|7|1B|8|@]|D|@]|E|$]]|$1|K|3|-4|5|6|7|1C|8|@]|D|@]|E|$]]|$1|L|3|M|5|N|7|1D|8|@$9|1E|A|1F|B|C]]|D|@$9|1G|A|1H|1|1I]]|E|$]]|$1|O|3|P|5|N|7|1J|8|@$9|1K|A|1L|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|1M|8|@]|D|@]|E|$]]|$1|R|3|-4|5|6|7|1N|8|@]|D|@]|E|$]]]|S|$T|$5|U|V|W|E|$X|Y]]]]

A while loop will execute the nested statement(s) repeatedly, as long as the while expression evaluates to <code>true</code>. 

The expression in your example <code>$info = mysql_fetch_object($data_jurisdiction)</code> checks whether the <code>$info</code>, the assigned value from <code>mysql_fetch_object()</code> is equal to true, after type juggling. 

It is important to understand two things here:

<ol>
<li><code>mysql_fetch_object()</code> returns the next row of the result set until the end of the data set is reached, where it returns false. See the <a href="http://php.net/manual/en/function.mysql-fetch-object.php" rel="nofollow">method documentation here</a>.</li>
<li>All assigned values of variables which are not equal to 0, or <code>null</code> evaluate to true after type juggling.</li>
</ol>

blocks|key|3161514|text|从手册中：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3161515|3161516|赋值表达式的值是赋值的值。也就是说，"$a+=+3“的值是3。|blockquote|3161517|3161518|3161519|同样来自关于mysql_fetch_array的手册：|3161520|3161521|返回与所读取的行相对应的字符串数组，如果没有更多的行，则返回FALSE。|3161522|3161523|3161524|因此，一旦没有更多的行，赋值将变成：|3161525|$info+=+false|code-block|syntax|javascript|3161526|在while条件中，它将被计算为false，从而导致循环终止。|3161527|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|10|8|@]|9|@]|A|$]]|$1|C|3|D|5|E|7|11|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|12|8|@]|9|@]|A|$]]|$1|G|3|-4|5|6|7|13|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|14|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|15|8|@]|9|@]|A|$]]|$1|K|3|L|5|E|7|16|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|17|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|18|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|19|8|@]|9|@]|A|$]]|$1|Q|3|R|5|S|7|1A|8|@]|9|@]|A|$T|U]]|$1|V|3|W|5|6|7|1B|8|@]|9|@]|A|$]]|$1|X|3|-4|5|6|7|1C|8|@]|9|@]|A|$]]]|Y|$]]

From the manual:

<blockquote>
 The value of an assignment expression is the value assigned. That is, the value of "$a = 3" is 3.
</blockquote>

Also from the manual about mysql_fetch_array:

<blockquote>
 Returns an array of strings that corresponds to the fetched row, or FALSE if there are no more rows.
</blockquote>

Therefore, once there are no more rows, the assignment will turn into:

<pre><code>$info = false
</code></pre>

Which will get evaluated as false in the while condition, causing the loop to terminate.

the code I'm looking at does this...

<pre><code>while ($info=mysql_fetch_array($data_jurisdiction))
{
//some stuff
}
</code></pre>

I'm wondering what does this while statement do? it has an assignment operator within it, so as long as $info gets assigned a value other than false, this code will execute?

while loop in php with assignment operator

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我看到的代码是这样做的……while ($info=mysql_fetch_array($data_jurisdiction)){//some stuff}我想知道这个while语句是做什么的？它有一个赋值操作符，所以只要$info被赋值为false以外的值，这段代码就会执行吗？

问使用赋值运算符的php中的while循环
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