blocks|key|756761|text|因为For-Each对象是cmdlet而不是循环，而continue和break不适用于它。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|756762|例如，如果您有：|756763|$b+=+1,2,3

foreach($a+in+$b)+{

++++$a+%7C+foreach+{+if+($_+-eq+2)+{continue;}+else+{Write-Host+$_}+}

++++Write-Host++"after"
}|code-block|syntax|javascript|756764|您将得到如下输出：|756765|1
after
3
after|756766|这是因为continue应用于外部foreach循环，而不是foreach对象cmdlet。在没有循环的情况下，最外面的级别，因此会给您一个印象，它的行为类似于break。|756767|那么，如何获得continue-like行为呢？一种方式当然是Where-Object：|756768|1..100+%7C+?{+$_+%25+7++-eq+0}+%7C+%25{Write-Host+$_+is+a+multiple+of+7}|756769|entityMap|0|LINK|mutability|MUTABLE|url|https://msdn.microsoft.com/powershell/reference/5.1/microsoft.powershell.core/Where-Object^0|2|8|Q|8|Z|5|0|0|0|0|0|4|8|28|5|0|7|8|V|C|0|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@$9|15|A|16|B|C]|$9|17|A|18|B|C]|$9|19|A|1A|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1B|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|1C|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|1D|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|1E|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|1F|8|@$9|1G|A|1H|B|C]|$9|1I|A|1J|B|C]]|D|@]|E|$]]|$1|S|3|T|5|6|7|1K|8|@$9|1L|A|1M|B|C]]|D|@$9|1N|A|1O|1|1P]]|E|$]]|$1|U|3|V|5|J|7|1Q|8|@]|D|@]|E|$K|L]]|$1|W|3|-4|5|6|7|1R|8|@]|D|@]|E|$]]]|X|$Y|$5|Z|10|11|E|$12|13]]]]

Because <code>For-Each</code> object is a cmdlet and not a loop and <code>continue</code> and <code>break</code> do not apply to it.

For example, if you have:

<pre><code>$b = 1,2,3

foreach($a in $b) {

 $a | foreach { if ($_ -eq 2) {continue;} else {Write-Host $_} }

 Write-Host "after"
}
</code></pre>

You will get output as:

<pre><code>1
after
3
after
</code></pre>

It is because the <code>continue</code> gets applied to the outer foreach loop and not the foreach-object cmdlet. In absence of a loop, the outermost level, hence giving you an impression of it acting like <code>break</code>.

So how do you get a <code>continue</code>-like behaviour? One way is <a href="https://msdn.microsoft.com/powershell/reference/5.1/microsoft.powershell.core/Where-Object" rel="noreferrer">Where-Object</a> of course:

<pre><code>1..100 | ?{ $_ % 7 -eq 0} | %{Write-Host $_ is a multiple of 7}
</code></pre>

blocks|key|540330|text|另一种选择是一种hack，但你可以将你的代码块包装在一个只执行一次的循环中。这样，continue将具有所需的效果：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|540331|1..100+%7C+ForEach-Object+{
++++for+($cont=$true;+$cont;+$cont=$false)+{
++++++++if+($_+%25+7+-ne+0+)+{+continue;+}
++++++++Write-Host+"$($_)+is+a+multiple+of+7"
++++}
}|code-block|syntax|javascript|540332|entityMap^0|15|8|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

Another alternative is kind of a hack, but you can wrap your block in a loop that will execute once. That way, <code>continue</code> will have the desired effect:

<pre><code>1..100 | ForEach-Object {
 for ($cont=$true; $cont; $cont=$false) {
 if ($_ % 7 -ne 0 ) { continue; }
 Write-Host "$($_) is a multiple of 7"
 }
}
</code></pre>

blocks|key|756903|text|只需使用return而不是continue。此return从ForEach-Object在特定迭代中调用的脚本块返回，因此，它在循环中模拟continue。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|756904|1..100+%7C+ForEach-Object+{
++++if+($_+%25+7+-ne+0+)+{+return+}
++++Write-Host+"$($_)+is+a+multiple+of+7"
}|code-block|syntax|javascript|756905|在重构时，有一个问题需要牢记。有时，人们希望使用ForEach-Object+cmdlet将foreach语句块转换为管道(它甚至具有别名foreach，这有助于简化转换，也容易出错)。所有continue都应替换为return。|756906|附言:不幸的是，在ForEach-Object中模拟break并非易事。|756907|entityMap^0|4|6|D|8|N|6|U|E|1X|8|0|0|O|E|1A|7|1X|7|2N|8|30|6|0|9|E|Q|5|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|11|8|@]|D|@]|E|$I|J]]|$1|K|3|L|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|C]|$9|1B|A|1C|B|C]]|D|@]|E|$]]|$1|M|3|N|5|6|7|1D|8|@$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|1I|8|@]|D|@]|E|$]]]|P|$]]

Simply use the <code>return</code> instead of the <code>continue</code>. This <code>return</code> returns from the script block which is invoked by <code>ForEach-Object</code> on a particular iteration, thus, it simulates the <code>continue</code> in a loop.

<pre><code>1..100 | ForEach-Object {
 if ($_ % 7 -ne 0 ) { return }
 Write-Host "$($_) is a multiple of 7"
}
</code></pre>

There is a gotcha to be kept in mind when refactoring. Sometimes one wants to convert a <code>foreach</code> statement block into a pipeline with a <code>ForEach-Object</code> cmdlet (it even has the alias <code>foreach</code> that helps to make this conversion easy and make mistakes easy, too). All <code>continue</code>s should be replaced with <code>return</code>.

P.S.: Unfortunately, it is not that easy to simulate <code>break</code> in <code>ForEach-Object</code>.

blocks|key|540468|text|一条简单的else语句使其工作方式如下所示：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|540469|1..100+%7C+ForEach-Object+{
++++if+($_+%25+7+-ne+0+)+{
++++++++#+Do+nothing
++++}+else+{
++++++++Write-Host+"$($_)+is+a+multiple+of+7"
++++}
}|code-block|syntax|javascript|540470|或在单个管道中：|540471|1..100+%7C+ForEach-Object+{+if+($_+%25+7+-ne+0+)+{}+else+{Write-Host+"$($_)+is+a+multiple+of+7"}}|540472|但更优雅的解决方案是反转您的测试，只为成功生成输出|540473|1..100+%7C+ForEach-Object+{if+($_+%25+7+-eq+0+)+{Write-Host+"$($_)+is+a+multiple+of+7"}}|540474|entityMap^0|5|4|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|Y|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|Z|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|10|8|@]|D|@]|E|$]]|$1|Q|3|R|5|H|7|11|8|@]|D|@]|E|$I|J]]|$1|S|3|-4|5|6|7|12|8|@]|D|@]|E|$]]]|T|$]]

A simple <code>else</code> statement makes it work as in:

<pre><code>1..100 | ForEach-Object {
 if ($_ % 7 -ne 0 ) {
 # Do nothing
 } else {
 Write-Host "$($_) is a multiple of 7"
 }
}
</code></pre>

Or in a single pipeline:

<pre><code>1..100 | ForEach-Object { if ($_ % 7 -ne 0 ) {} else {Write-Host "$($_) is a multiple of 7"}}
</code></pre>

But a more elegant solution is to invert your test and generate output for only your successes

<pre><code>1..100 | ForEach-Object {if ($_ % 7 -eq 0 ) {Write-Host "$($_) is a multiple of 7"}}
</code></pre>

If I do the following in a PowerShell script:

<pre><code>$range = 1..100
ForEach ($_ in $range) {
 if ($_ % 7 -ne 0 ) { continue; }
 Write-Host "$($_) is a multiple of 7"
}
</code></pre>

I get the expected output of:

<pre><code>7 is a multiple of 7
14 is a multiple of 7
21 is a multiple of 7
28 is a multiple of 7
35 is a multiple of 7
42 is a multiple of 7
49 is a multiple of 7
56 is a multiple of 7
63 is a multiple of 7
70 is a multiple of 7
77 is a multiple of 7
84 is a multiple of 7
91 is a multiple of 7
98 is a multiple of 7
</code></pre>

However, if I use a pipeline and <code>ForEach-Object</code>, <code>continue</code> seems to break out of the pipeline loop.

<pre><code>1..100 | ForEach-Object {
 if ($_ % 7 -ne 0 ) { continue; }
 Write-Host "$($_) is a multiple of 7"
}
</code></pre>

Can I get a <code>continue</code>-like behavior while still doing ForEach-Object, so I don't have to breakup my pipeline?

Why does 'continue' behave like 'break' in a Foreach-Object?

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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如果我在PowerShell脚本中执行以下操作：$range = 1..100ForEach ($_ in $range) {    if ($_ % 7 -ne 0 ) { continue; }    Write-Host "$($_) is a multiple of 7"}我得到了以下内容的预期输出：7 is ...

问为什么'continue‘在Foreach-Object中的行为类似于'break’？
EN

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问为什么'continue‘在Foreach-Object中的行为类似于'break’？EN