blocks|key|5236820|text|将函数外部的计数器变量定义为GLOBAL，并在函数内部增加。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|5236821|entityMap^0|E|6|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|$]]

Define the counter-Variable outside the function as <code>GLOBAL</code> and increase inside the function.

blocks|key|5236832|text|您可以向递归函数添加另一个参数，该参数将用作计数器：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5236833|function+structure($x,+$cnt)+{
++++$qry+=+mysql_query("SELECT+`parent_id`+FROM+`categories`+WHERE+`categories_id`=$x");
++++$result+=+mysql_fetch_assoc($qry);
++++$cat+=+$result['parent_id'];
++++if($cat+!=0)+{
++++++++structure($cat,+$cnt%2B%2B);
++++}
++++echo+$cat.'+>';
}|code-block|syntax|javascript|5236834|或者，您可以使用全局变量。|5236835|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You can add another parameter to your recursive function, which will serve as a counter:

<pre><code>function structure($x, $cnt) {
 $qry = mysql_query("SELECT `parent_id` FROM `categories` WHERE `categories_id`=$x");
 $result = mysql_fetch_assoc($qry);
 $cat = $result['parent_id'];
 if($cat !=0) {
 structure($cat, $cnt++);
 }
 echo $cat.' &gt;';
}
</code></pre>

or you could use a global variable.

blocks|key|2183570|text|使用static变量。比如|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2183571|function+structure($x)+{
+++++static+$counter+=+0;
++++/*+your+code+*/
++++$counter%2B%2B;
}|code-block|syntax|javascript|2183572|entityMap^0|2|6|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|$]]

use <code>static</code> variables. such as

<pre><code>function structure($x) {
 static $counter = 0;
 /* your code */
 $counter++;
}
</code></pre>

blocks|key|2176945|text|使用引用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2176946|function+structure($x,+&$i)+{
++++$i%2B%2B;
++++$qry+=+mysql_query("SELECT+`parent_id`+FROM+`categories`+WHERE+`categories_id`=$x");
++++$result+=+mysql_fetch_assoc($qry);
++++$cat+=+$result['parent_id'];
++++if($cat+!=0)+{
++++++++structure($cat,+$i);
++++}
++++echo+$cat.'+>';
}



$i+=+0;
structure($var,$i);
var_dump($i);|code-block|syntax|javascript|2176947|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|$]]

Use references :

<pre><code>function structure($x, &amp;$i) {
 $i++;
 $qry = mysql_query("SELECT `parent_id` FROM `categories` WHERE `categories_id`=$x");
 $result = mysql_fetch_assoc($qry);
 $cat = $result['parent_id'];
 if($cat !=0) {
 structure($cat, $i);
 }
 echo $cat.' &gt;';
}



$i = 0;
structure($var,$i);
var_dump($i);
</code></pre>

blocks|key|3124451|text|当我遇到这个问题时，我通常的解决方案是添加一个计数器变量作为额外的参数，例如|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3124452|function+structure($x,+$i=0)+{
++++...
++++structure($nextX,+%2B%2B$i);
++++...
}|code-block|syntax|javascript|3124453|这样做的好处是，对structure的原始调用不需要您指定计数器，并且仍然可以像structure($x);一样调用计数器|offset|length|style|CODE|3124454|entityMap^0|0|0|9|9|14|E|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]|$I|T|J|U|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|N|$]]

My usual solution to this problem when I'm faced with it is to add a counter variable as an extra parameter, e.g.

<pre><code>function structure($x, $i=0) {
 ...
 structure($nextX, ++$i);
 ...
}
</code></pre>

This has the benefit that the original call to <code>structure</code> does not require you to specify the counter, and such can still be called as <code>structure($x);</code>

blocks|key|3124459|text|选项1:通过引用传递变量|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3124460|function+structure($cat,+&$counter)+{
++++$counter%2B%2B;
++++...
}

structure('foo',+$counter);

echo+$counter;|code-block|syntax|javascript|3124461|选项2:使用static变量|offset|length|style|CODE|3124462|function+structure($cat)+{
++++static+$counter+=+0;
++++echo+%2B%2B$counter;
++++...
}|3124463|选项3:使用global变量(不，不！)|3124464|$counter+=+0;

function+structure($cat)+{
++++global+$counter;
++++$counter%2B%2B;
++++...
}|3124465|选项4:使用闭包|3124466|$counter+=+0;

$structure+=+function+($cat)+use+(&$counter)+{
++++$counter%2B%2B;
++++...
}

$structure('foo');
echo+$counter;|3124467|entityMap^0|0|0|6|6|0|0|6|6|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|10|8|@$I|11|J|12|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|14|8|@$I|15|J|16|K|L]]|9|@]|A|$]]|$1|Q|3|R|5|D|7|17|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|18|8|@]|9|@]|A|$]]|$1|U|3|V|5|D|7|19|8|@]|9|@]|A|$E|F]]|$1|W|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|X|$]]

Option 1: pass in a variable by reference

<pre><code>function structure($cat, &amp;$counter) {
 $counter++;
 ...
}

structure('foo', $counter);

echo $counter;
</code></pre>

Option 2: use a <code>static</code> variable

<pre><code>function structure($cat) {
 static $counter = 0;
 echo ++$counter;
 ...
}
</code></pre>

Option 3: use a <code>global</code> variable (no no!)

<pre><code>$counter = 0;

function structure($cat) {
 global $counter;
 $counter++;
 ...
}
</code></pre>

Option 4: use a closure

<pre><code>$counter = 0;

$structure = function ($cat) use (&amp;$counter) {
 $counter++;
 ...
}

$structure('foo');
echo $counter;
</code></pre>

blocks|key|2183609|text|您有许多选择。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2183610|最简单的是：|2183611|2183612|您可以添加静态变量|unordered-list-item|2183613|您可以将counter作为附加变量传递。|2183614|2183615|不太明显和更复杂的解决方案可能包括使用Registry和/或Singleton模式。|2183616|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|E|3|F|5|G|7|R|8|@]|9|@]|A|$]]|$1|H|3|I|5|G|7|S|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|T|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|N|$]]

You have number of options.

The simplest are:

<ul>
<li>you can add static variable</li>
<li>you can pass counter as additional variable.</li>
</ul>

Less obvious and more complicated solutions may include using Registry and/or Singleton patterns.

blocks|key|5236986|text|尝尝这个|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5236987|//+function+Counter+
$cnt+=+0;

function+structure($x)+{


global+$cnt;

$cnt+%2B=+1;

$qry+=+mysql_query("SELECT+`parent_id`+FROM+`categories`+WHERE+`categories_id`=$x");
$result+=+mysql_fetch_assoc($qry);
$cat+=+$result['parent_id'];
if($cat+!=0)+{
++++structure($cat);
}
echo+$cat.'+>';
}|code-block|syntax|javascript|5236988|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|$]]

try this

<pre><code>// function Counter 
$cnt = 0;

function structure($x) {


global $cnt;

$cnt += 1;

$qry = mysql_query("SELECT `parent_id` FROM `categories` WHERE `categories_id`=$x");
$result = mysql_fetch_assoc($qry);
$cat = $result['parent_id'];
if($cat !=0) {
 structure($cat);
}
echo $cat.' &gt;';
}
</code></pre>

I need to know how many times a recursive function is called within the function. This is my function:

<pre><code>function structure($x) {
$qry = mysql_query("SELECT `parent_id` FROM `categories` WHERE `categories_id`=$x");
$result = mysql_fetch_assoc($qry);
$cat = $result['parent_id'];
if($cat !=0) {
 structure($cat);
}
echo $cat.' &gt;';
}
</code></pre>

I have tried adding a counter, e.g. $i=0, then $i++, but it will of course revert back to the $i=0 every time the function is called. I have tried adding arrays, and counting the arrays, but of course it has to set a new array, $i=array(), every time the function is called. 

The one way I can think might work is if I set the array or counter outside of the function, but I don't know if its possible to call a variable in a function that is outside the function.

Any ideas on how to call a variable outside a function or even a better way to count the times the function is called?

counting the number of times a recursive function is called

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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我需要知道一个递归函数在函数中被调用了多少次。这是我的函数：function structure($x) {$qry = mysql_query("SELECT `parent_id` FROM `categories` WHERE `categories_id`=$x");$result = mysql_fetch_...

问计算递归函数被调用的次数
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问计算递归函数被调用的次数EN