blocks|key|1347109|text|是的，它很好-就像在if语句中使用它一样。当然，您不能使用break从交换机内部中断循环。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1347110|entityMap^0|A|2|T|5|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

Yes, it's OK - it's just like using it in an <code>if</code> statement. Of course, you can't use a <code>break</code> to break out of a loop from inside a switch.

blocks|key|1347175|text|这很好，continue语句与封闭循环相关，并且您的代码应该等价于(避免这样的跳转语句)：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1347176|while+(something+=+get_something())+{
++++if+(something+==+A+%7C%7C+something+==+B)
++++++++do_something();
}|code-block|syntax|javascript|1347177|但是，如果您希望break像您的注释所建议的那样退出循环(它总是再次尝试另一个东西，直到计算结果为false)，那么您将需要一个不同的结构。|1347178|例如：|1347179|do+{
++++something+=+get_something();
}+while+(!(something+==+A+%7C%7C+something+==+B));
do_something();|1347180|entityMap^0|4|8|0|0|8|5|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|Z|8|@]|D|@]|E|$]]|$1|O|3|P|5|H|7|10|8|@]|D|@]|E|$I|J]]|$1|Q|3|-4|5|6|7|11|8|@]|D|@]|E|$]]]|R|$]]

It's fine, the <code>continue</code> statement relates to the enclosing loop, and your code should be equivalent to (avoiding such jump statements):

<pre><code>while (something = get_something()) {
 if (something == A || something == B)
 do_something();
}
</code></pre>

But if you expect <code>break</code> to exit the loop, as your comment suggest (it always tries again with another something, until it evaluates to false), you'll need a different structure.

For example:

<pre><code>do {
 something = get_something();
} while (!(something == A || something == B));
do_something();
</code></pre>

blocks|key|1131795|text|虽然在技术上是有效的，但所有这些跳转都模糊了控制流--尤其是continue语句。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1131796|我会使用这样的技巧作为最后的手段，而不是第一个。|1131797|怎么样|1131798|while+(something+=+get_something())
{
++++switch+(something)
++++{
++++case+A:
++++case+B:
++++++++do_something();
++++}++++++++
}|code-block|syntax|javascript|1131799|它更短，并以更清晰的方式执行其内容。|1131800|entityMap^0|U|8|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|V|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|W|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|X|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|Y|8|@]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|R|$]]

While technically valid, all these jumps obscure control flow -- especially the <code>continue</code> statement.

I would use such a trick as a last resort, not first one.

How about

<pre><code>while (something = get_something())
{
 switch (something)
 {
 case A:
 case B:
 do_something();
 } 
}
</code></pre>

It's shorter and perform its stuff in a more clear way.

blocks|key|1347302|text|它在语法上是正确的，在风格上也是正确的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1347303|好的风格要求每条case:语句都应该以以下其中一项结尾：|offset|length|style|CODE|1347304|+break;
+continue;
+return+(x);
+exit+(x);
+throw+(x);
+//fallthrough|code-block|syntax|javascript|1347305|此外，在case+(x):之后立即使用|1347306|+case+(y):
+default:|1347307|是允许的-捆绑几个具有完全相同效果的案例。|1347308|其他任何东西都被怀疑是错误的，就像if(a=4){...}一样，当然你需要闭合循环(while，for，do...while)才能让continue工作。它不会单独循环回case()。而是像这样的构造：|1347309|while(record+=+getNewRecord())
{
++++switch(record.type)
++++{
++++++++case+RECORD_TYPE_...;
++++++++++++...
++++++++break;
++++++++default:+//unknown+type
++++++++++++continue;+//skip+processing+this+record+altogether.
++++}
++++//...more+processing...
}|1347310|好的，...is。|1347311|entityMap^0|0|8|5|0|0|4|9|0|0|0|H|C|16|5|1C|3|1G|A|1U|8|2D|6|0|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|11|8|@$D|12|E|13|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|14|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|15|8|@$D|16|E|17|F|G]]|9|@]|A|$]]|$1|O|3|P|5|J|7|18|8|@]|9|@]|A|$K|L]]|$1|Q|3|R|5|6|7|19|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|1A|8|@$D|1B|E|1C|F|G]|$D|1D|E|1E|F|G]|$D|1F|E|1G|F|G]|$D|1H|E|1I|F|G]|$D|1J|E|1K|F|G]|$D|1L|E|1M|F|G]]|9|@]|A|$]]|$1|U|3|V|5|J|7|1N|8|@]|9|@]|A|$K|L]]|$1|W|3|X|5|6|7|1O|8|@]|9|@]|A|$]]|$1|Y|3|-4|5|6|7|1P|8|@]|9|@]|A|$]]]|Z|$]]

It's syntactically correct and stylistically okay.

Good style requires every <code>case:</code> statement should end with one of the following:

<pre><code> break;
 continue;
 return (x);
 exit (x);
 throw (x);
 //fallthrough
</code></pre>

Additionally, following <code>case (x):</code> immediately with

<pre><code> case (y):
 default:
</code></pre>

is permissible - bundling several cases that have exactly the same effect.

Anything else is suspected to be a mistake, just like <code>if(a=4){...}</code>
Of course you need enclosing loop (<code>while</code>, <code>for</code>, <code>do...while</code>) for <code>continue</code> to work. It won't loop back to <code>case()</code> alone. But a construct like:

<pre><code>while(record = getNewRecord())
{
 switch(record.type)
 {
 case RECORD_TYPE_...;
 ...
 break;
 default: //unknown type
 continue; //skip processing this record altogether.
 }
 //...more processing...
}
</code></pre>

...is okay.

I want to jump from the middle of a <code>switch</code> statement, to the loop statement in the following code:

<pre><code>while (something = get_something())
{
 switch (something)
 {
 case A:
 case B:
 break;
 default:
 // get another something and try again
 continue;
 }
 // do something for a handled something
 do_something();
}
</code></pre>

Is this a valid way to use <code>continue</code>? Are <code>continue</code> statements ignored by <code>switch</code> statements? Do C and C++ differ on their behaviour here?

Using continue in a switch statement

我想从switch语句的中间跳到以下代码中的循环语句：while (something = get_something()){    switch (something)    {    case A:    case B:        break;    default:        // get another...

问在switch语句中使用continue
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