blocks|key|4294051|text|让我考虑另一种方法，大多数开发人员都认为这种方法比使用变量更好：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4294052|//array+for+the+protein_feed's
++++$protein_feed=array('low'=>'1','moderate'=>'2','high'=>'3');+
//then+to+select+one+based+on+the+value+of+$repeater
++++echo+$protein_feed[$repeater];|code-block|syntax|javascript|4294053|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|$]]

let me purpose an alternative approach, one that most developers agree is better than using variable variables:

<pre><code>//array for the protein_feed's
 $protein_feed=array('low'=&gt;'1','moderate'=&gt;'2','high'=&gt;'3'); 
//then to select one based on the value of $repeater
 echo $protein_feed[$repeater];
</code></pre>

blocks|key|4293904|text|我认为您希望这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4293905|<?php

//+Example+-+though+you+should+use+objects,+key+->+values,+
//+arrays+instead+in+my+opinion.

$low_protein_feed+=+"Low+protein";
$moderate_protein_feed+=+"Lots+of+protein";
$high_protein_feed+=+"high+grade+protein";

$types+=+array("low",+"moderate",+"high");

foreach($types+as+$type)+{

++++echo+${$type+.+'_protein_feed'}+.+"+\n";

}|code-block|syntax|javascript|4293906|输出：|4293907|$+php+testme.php+
Low+protein+
Lots+of+protein+
high+grade+protein+|4293908|然而，你真的应该使用这样的东西：|4293909|$types+=+array("low",+"moderate",+"high");
$proteins=array('low'=>'1','moderate'=>'2','high'=>'3');+

foreach($types+as+$type)+{
++++echo+$proteins[$type];
}|4293910|更高级的设计，你可以使用对象，并声明一个类型的对象，并使用一个标准类型的项目。|4293911|在这里进一步阅读动态变量名称以及PHP5/7之间的差异：|4293912|Using+braces+with+dynamic+variable+names+in+PHP|offset|length|4293913|http://www.dummies.com/programming/php/how-to-use-php-variable-variables/|4293914|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/9257505/using-braces-with-dynamic-variable-names-in-php|1^0|0|0|0|0|0|0|0|0|0|1B|0|0|0|21|1|0^^$0|@$1|2|3|4|5|6|7|17|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|18|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|19|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|1A|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|1B|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|1C|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1D|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1E|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|1F|8|@]|9|@$U|1G|V|1H|1|1I]]|A|$]]|$1|W|3|X|5|6|7|1J|8|@]|9|@$U|1K|V|1L|1|1M]]|A|$]]|$1|Y|3|-4|5|6|7|1N|8|@]|9|@]|A|$]]]|Z|$10|$5|11|12|13|A|$14|15]]|16|$5|11|12|13|A|$14|X]]]]

I think you are looking to do something like this:

<pre><code>&lt;?php

// Example - though you should use objects, key -&gt; values, 
// arrays instead in my opinion.

$low_protein_feed = "Low protein";
$moderate_protein_feed = "Lots of protein";
$high_protein_feed = "high grade protein";

$types = array("low", "moderate", "high");

foreach($types as $type) {

 echo ${$type . '_protein_feed'} . " \n";

}
</code></pre>

Output:

<pre><code>$ php testme.php 
Low protein 
Lots of protein 
high grade protein 
</code></pre>

However, you should really use something like this:

<pre><code>$types = array("low", "moderate", "high");
$proteins=array('low'=&gt;'1','moderate'=&gt;'2','high'=&gt;'3'); 

foreach($types as $type) {
 echo $proteins[$type];
}
</code></pre>

More advanced design, you can use objects and declare a type of said object and use a standard type for projects. 

Further reading on dynamic variable names here and the differences between PHP5/7 :

<a href="https://stackoverflow.com/questions/9257505/using-braces-with-dynamic-variable-names-in-php">Using braces with dynamic variable names in PHP</a>

<a href="http://www.dummies.com/programming/php/how-to-use-php-variable-variables/" rel="nofollow noreferrer">http://www.dummies.com/programming/php/how-to-use-php-variable-variables/</a>

I have a variable called $repeater, which will either be low, moderate or high.

I also have variables called...

<pre><code>$low_protein_feed
$moderate_protein_feed
$high_protein_feed
</code></pre>

I want to call one of these variables depending on what the value of $repeater is.

I got as far as this...

<pre><code>echo "${$repeater}_protein_feed";
</code></pre>

...which outputs moderate_protein_feed, for example. But it echoes as text, when I want it to be echoing the value of $moderate_protein_feed variable.

I feel like I'm not far off. 
Thanks for any input

Use a PHP variable as part of another variable name

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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我有一个名为$repeater的变量，它可以是低、中或高。我还有一个变量叫做...$low_protein_feed$moderate_protein_feed$high_protein_feed我想根据$repeater的值来调用其中一个变量。我已经走到这一步了。echo "${$repeater}_protein_...

问使用PHP变量作为另一个变量名的一部分
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