func_array_extract.asp

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    <td valign="top">extract_rules</td>
    <td valign="top">Optional. The extract() function checks for invalid 
	variable names and collisions with existing variable names. This parameter 
	specifies how invalid and colliding names are treated.<p>Possible values:</p>
	<ul>
		<li>EXTR_OVERWRITE - Default. On collision, the existing variable is 
		overwritten</li>
		<li>EXTR_SKIP - On collision, the existing variable is not overwritten</li>
		<li>EXTR_PREFIX_SAME - On collision, the variable name will be given a 
		prefix</li>
		<li>EXTR_PREFIX_ALL - All variable names will be given a prefix</li>
		<li>EXTR_PREFIX_INVALID - Only invalid or numeric variable names will be 
		given a prefix</li>
		<li>EXTR_IF_EXISTS - Only overwrite existing variables in the current 
		symbol table, otherwise do nothing</li>
		<li>EXTR_PREFIX_IF_EXISTS - Only add prefix to variables if the same 
		variable exists in the current symbol table</li>
		<li>EXTR_REFS - Extracts variables as references. The imported variables 
		are still referencing the values of the array parameter</li>
	</ul>
    </td>
  </tr>
  <tr>
    <td valign="top">prefix</td>
    <td valign="top">Optional. If EXTR_PREFIX_SAME, EXTR_PREFIX_ALL, 
	EXTR_PREFIX_INVALID or EXTR_PREFIX_IF_EXISTS are used in the extract_rules 
	parameter, a specified prefix is required.
    <p>This parameter specifies the prefix. The prefix is automatically 
	separated from the array key by an underscore character.</td>
  </tr>
  </table>
<br />


<hr />

<h2>Example 1</h2>

<table class="ex" cellspacing="0" border="1" width="100%" id="table17">
  <tr>
    <td>
    <pre>&lt;?php
$a = 'Original';
$my_array = array(&quot;a&quot; =&gt; &quot;Cat&quot;,&quot;b&quot; =&gt; &quot;Dog&quot;, &quot;c&quot; =&gt; &quot;Horse&quot;);
extract($my_array);
echo &quot;\$a = $a; \$b = $b; \$c = $c&quot;;
?&gt;</pre>
    </td>
</tr>
</table>

<p>The output of the code above will be:</p>

<table class="ex" cellspacing="0" border="1" width="100%" id="table18">
  <tr>
    <td>
    <pre>$a = Cat; $b = Dog; $c = Horse</pre>
    </td>
</tr>
</table>

<br />


<hr />

<h2>Example 2</h2>
<p>With all parameters in use:</p>

<table class="ex" cellspacing="0" border="1" width="100%" id="table13">
  <tr>
    <td>
    <pre>&lt;?php
$a = 'Original';
$my_array = array(&quot;a&quot; =&gt; &quot;Cat&quot;,&quot;b&quot; =&gt; &quot;Dog&quot;, &quot;c&quot; =&gt; &quot;Horse&quot;);

extract($my_array, EXTR_PREFIX_SAME, 'dup');

echo &quot;\$a = $a; \$b = $b; \$c = $c; \$dup_a = $dup_a;&quot;;
?&gt;</pre>
    </td>
</tr>
</table>

<p>The output of the code above will be:</p>

<table class="ex" cellspacing="0" border="1" width="100%" id="table14">
  <tr>
    <td>
    <pre>$a = Original; $b = Dog; $c = Horse; $dup_a = Cat;</pre>
    </td>
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