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php-manual-ro-20051028-1.noarch.rpm

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>Manual PHP</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="language.variables.predefined.html"
ACCESSKEY="P"
>Înapoi</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
>Cap. 7. Variables</TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="language.variables.variable.html"
ACCESSKEY="N"
>Înainte</A
></TD
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><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="sect1"
><H1
CLASS="sect1"
><A
NAME="language.variables.scope"
>Variable scope</A
></H1
><P
>&#13;    The scope of a variable is the context within which it is defined.
    For the most part all PHP variables only have a single scope.
    This single scope spans included and required files as well.  For
    example:
   </P
><DIV
CLASS="informalexample"
><P
></P
><A
NAME="AEN1555"
></A
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br />$a </font><font color="#007700">= </font><font color="#0000BB">1</font><font color="#007700">;<br />include </font><font color="#DD0000">"b.inc"</font><font color="#007700">;<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
><P
></P
></DIV
><P
>&#13;    Here the <VAR
CLASS="varname"
>$a</VAR
> variable will be available within
    the included <TT
CLASS="filename"
>b.inc</TT
> script.  However, within
    user-defined functions a local function scope is introduced.  Any
    variable used inside a function is by default limited to the local
    function scope.  For example:
   </P
><DIV
CLASS="informalexample"
><P
></P
><A
NAME="AEN1560"
></A
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br />$a </font><font color="#007700">= </font><font color="#0000BB">1</font><font color="#007700">; </font><font color="#FF8000">/* global scope */ <br /><br /></font><font color="#007700">function </font><font color="#0000BB">Test</font><font color="#007700">()<br />{ <br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#0000BB">$a</font><font color="#007700">; </font><font color="#FF8000">/* reference to local scope variable */ <br /></font><font color="#007700">} <br /><br /></font><font color="#0000BB">Test</font><font color="#007700">();<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
><P
></P
></DIV
><P
>&#13;    This script will not produce any output because the echo statement
    refers to a local version of the <VAR
CLASS="varname"
>$a</VAR
> variable,
    and it has not been assigned a value within this scope.  You may
    notice that this is a little bit different from the C language in
    that global variables in C are automatically available to
    functions unless specifically overridden by a local definition.
    This can cause some problems in that people may inadvertently
    change a global variable.  In PHP global variables must be
    declared global inside a function if they are going to be used in
    that function.
   </P
><DIV
CLASS="sect2"
><H2
CLASS="sect2"
><A
NAME="language.variables.scope.global"
>The global keyword</A
></H2
><P
>&#13;     First, an example use of <VAR
CLASS="literal"
>global</VAR
>:
    </P
><P
>&#13;     <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN1569"
></A
><P
><B
>Exemplu 7-1. Using global</B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br />$a </font><font color="#007700">= </font><font color="#0000BB">1</font><font color="#007700">;<br /></font><font color="#0000BB">$b </font><font color="#007700">= </font><font color="#0000BB">2</font><font color="#007700">;<br /><br />function </font><font color="#0000BB">Sum</font><font color="#007700">()<br />{<br />&nbsp;&nbsp;&nbsp;&nbsp;global </font><font color="#0000BB">$a</font><font color="#007700">, </font><font color="#0000BB">$b</font><font color="#007700">;<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$b </font><font color="#007700">= </font><font color="#0000BB">$a </font><font color="#007700">+ </font><font color="#0000BB">$b</font><font color="#007700">;<br />} <br /><br /></font><font color="#0000BB">Sum</font><font color="#007700">();<br />echo </font><font color="#0000BB">$b</font><font color="#007700">;<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
    </P
><P
>&#13;    The above script will output "3".  By declaring
    <VAR
CLASS="varname"
>$a</VAR
> and <VAR
CLASS="varname"
>$b</VAR
> global within the
    function, all references to either variable will refer to the
    global version.  There is no limit to the number of global
    variables that can be manipulated by a function.
   </P
><P
>&#13;    A second way to access variables from the global scope is to use
    the special PHP-defined <VAR
CLASS="varname"
>$GLOBALS</VAR
> array.  The
    previous example can be rewritten as:
   </P
><P
>&#13;    <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN1578"
></A
><P
><B
>Exemplu 7-2. Using <VAR
CLASS="varname"
>$GLOBALS</VAR
> instead of global</B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br />$a </font><font color="#007700">= </font><font color="#0000BB">1</font><font color="#007700">;<br /></font><font color="#0000BB">$b </font><font color="#007700">= </font><font color="#0000BB">2</font><font color="#007700">;<br /><br />function </font><font color="#0000BB">Sum</font><font color="#007700">()<br />{<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$GLOBALS</font><font color="#007700">[</font><font color="#DD0000">"b"</font><font color="#007700">] = </font><font color="#0000BB">$GLOBALS</font><font color="#007700">[</font><font color="#DD0000">"a"</font><font color="#007700">] + </font><font color="#0000BB">$GLOBALS</font><font color="#007700">[</font><font color="#DD0000">"b"</font><font color="#007700">];<br />} <br /><br /></font><font color="#0000BB">Sum</font><font color="#007700">();<br />echo </font><font color="#0000BB">$b</font><font color="#007700">;<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
   </P
><P
>&#13;    The <VAR
CLASS="varname"
>$GLOBALS</VAR
> array is an associative array with
    the name of the global variable being the key and the contents of
    that variable being the value of the array element.
    Notice how <VAR
CLASS="varname"
>$GLOBALS</VAR
> exists in any scope, this 
    is because $GLOBALS is a <A
HREF="language.variables.predefined.html#language.variables.superglobals"
>superglobal</A
>.
    Here's an example demonstrating the power of superglobals: 
   </P
><P
>&#13;    <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN1587"
></A
><P
><B
>Exemplu 7-3. Example demonstrating superglobals and scope</B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">function </font><font color="#0000BB">test_global</font><font color="#007700">()<br />{<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#FF8000">// Most predefined variables aren't "super" and require <br />&nbsp;&nbsp;&nbsp;&nbsp;// 'global' to be available to the functions local scope.<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#007700">global </font><font color="#0000BB">$HTTP_POST_VARS</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;<br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#0000BB">$HTTP_POST_VARS</font><font color="#007700">[</font><font color="#DD0000">'name'</font><font color="#007700">];<br />&nbsp;&nbsp;&nbsp;&nbsp;<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#FF8000">// Superglobals are available in any scope and do <br />&nbsp;&nbsp;&nbsp;&nbsp;// not require 'global'. Superglobals are available <br />&nbsp;&nbsp;&nbsp;&nbsp;// as of PHP 4.1.0<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#007700">echo </font><font color="#0000BB">$_POST</font><font color="#007700">[</font><font color="#DD0000">'name'</font><font color="#007700">];<br />}<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
   </P
></DIV
><DIV
CLASS="sect2"
><H2
CLASS="sect2"
><A
NAME="language.variables.scope.static"
>Using static variables</A
></H2
><P
>&#13;    Another important feature of variable scoping is the
    <SPAN
CLASS="emphasis"
><I
CLASS="emphasis"
>static</I
></SPAN
> variable.  A static variable exists
    only in a local function scope, but it does not lose its value
    when program execution leaves this scope.  Consider the following
    example:
   </P
><P
>&#13;    <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN1595"
></A
><P
><B
>Exemplu 7-4. Example demonstrating need for static variables</B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">function </font><font color="#0000BB">Test </font><font color="#007700">()<br />{<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$a </font><font color="#007700">= </font><font color="#0000BB">0</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#0000BB">$a</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$a</font><font color="#007700">++;<br />}<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
   </P
><P
>&#13;    This function is quite useless since every time it is called it
    sets <VAR
CLASS="varname"
>$a</VAR
> to <VAR
CLASS="literal"
>0</VAR
> and prints
    "0".  The <VAR
CLASS="varname"
>$a</VAR
>++ which increments the
    variable serves no purpose since as soon as the function exits the
    <VAR
CLASS="varname"
>$a</VAR
> variable disappears.  To make a useful
    counting function which will not lose track of the current count,
    the <VAR
CLASS="varname"
>$a</VAR
> variable is declared static:
   </P
><P
>&#13;    <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN1605"
></A
><P
><B
>Exemplu 7-5. Example use of static variables</B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">function </font><font color="#0000BB">Test</font><font color="#007700">()<br />{<br />&nbsp;&nbsp;&nbsp;&nbsp;static </font><font color="#0000BB">$a </font><font color="#007700">= </font><font color="#0000BB">0</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#0000BB">$a</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$a</font><font color="#007700">++;<br />}<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
   </P
><P
>&#13;    Now, every time the Test() function is called it will print the
    value of <VAR
CLASS="varname"
>$a</VAR
> and increment it.
   </P
><P
>&#13;    Static variables also provide one way to deal with recursive
    functions. A recursive function is one which calls itself.  Care
    must be taken when writing a recursive function because it is
    possible to make it recurse indefinitely.  You must make sure you
    have an adequate way of terminating the recursion.  The following
    simple function recursively counts to 10, using the static
    variable <VAR
CLASS="varname"
>$count</VAR
> to know when to stop:
   </P
><P
>&#13;    <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN1613"
></A
><P
><B
>Exemplu 7-6. Static variables with recursive functions</B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">function </font><font color="#0000BB">Test</font><font color="#007700">()<br />{<br />&nbsp;&nbsp;&nbsp;&nbsp;static </font><font color="#0000BB">$count </font><font color="#007700">= </font><font color="#0000BB">0</font><font color="#007700">;<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$count</font><font color="#007700">++;<br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#0000BB">$count</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;if (</font><font color="#0000BB">$count </font><font color="#007700">&lt; </font><font color="#0000BB">10</font><font color="#007700">) {<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">Test </font><font color="#007700">();<br />&nbsp;&nbsp;&nbsp;&nbsp;}<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$count</font><font color="#007700">--;<br />}<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
   </P
><DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Not&#227;: </B
>  
       Static variables maybe declared as seen in the examples above. 
       Trying to assign values to these variables which are the 
       result of expressions will cause a parse error.
     </P
><P
>  
      <TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
CLASS="EXAMPLE"
><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN1619"
></A
><P
><B
>Exemplu 7-7. Declaring static variables</B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">function </font><font color="#0000BB">foo</font><font color="#007700">(){<br />&nbsp;&nbsp;&nbsp;&nbsp;static </font><font color="#0000BB">$int </font><font color="#007700">= </font><font color="#0000BB">0</font><font color="#007700">;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#FF8000">// correct <br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#007700">static </font><font color="#0000BB">$int </font><font color="#007700">= </font><font color="#0000BB">1</font><font color="#007700">+</font><font color="#0000BB">2</font><font color="#007700">;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#FF8000">// wrong&nbsp;&nbsp;(as it is an expression)<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#007700">static </font><font color="#0000BB">$int </font><font color="#007700">= </font><font color="#0000BB">sqrt</font><font color="#007700">(</font><font color="#0000BB">121</font><font color="#007700">);&nbsp;&nbsp;</font><font color="#FF8000">// wrong&nbsp;&nbsp;(as it is an expression too)<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$int</font><font color="#007700">++;<br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#0000BB">$int</font><font color="#007700">;<br />}<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
>
    </P
></BLOCKQUOTE
></DIV
></DIV
><DIV
CLASS="sect2"
><H2
CLASS="sect2"
><A
NAME="language.variables.scope.references"
>References with global and static variables</A
></H2
><P
>&#13;    The Zend Engine 1, driving <VAR
CLASS="literal"
>PHP 4</VAR
>, implements the
    <A
HREF="language.variables.scope.html#language.variables.scope.static"
>static</A
> and 
    <A
HREF="language.variables.scope.html#language.variables.scope.global"
>global</A
> modifier 
    for variables in terms of <A
HREF="language.references.html"
>&#13;    references</A
>. For example, a true global variable
    imported inside a function scope with the <VAR
CLASS="literal"
>global</VAR
>
    statement actually creates a reference to the global variable. This can
    lead to unexpected behaviour which the following example addresses:
   </P
><DIV
CLASS="informalexample"
><P
></P
><A
NAME="AEN1630"
></A
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">function </font><font color="#0000BB">test_global_ref</font><font color="#007700">() {<br />&nbsp;&nbsp;&nbsp;&nbsp;global </font><font color="#0000BB">$obj</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$obj </font><font color="#007700">= &amp;new </font><font color="#0000BB">stdclass</font><font color="#007700">;<br />}<br /><br />function </font><font color="#0000BB">test_global_noref</font><font color="#007700">() {<br />&nbsp;&nbsp;&nbsp;&nbsp;global </font><font color="#0000BB">$obj</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$obj </font><font color="#007700">= new </font><font color="#0000BB">stdclass</font><font color="#007700">;<br />}<br /><br /></font><font color="#0000BB">test_global_ref</font><font color="#007700">();<br /></font><font color="#0000BB">var_dump</font><font color="#007700">(</font><font color="#0000BB">$obj</font><font color="#007700">);<br /></font><font color="#0000BB">test_global_noref</font><font color="#007700">();<br /></font><font color="#0000BB">var_dump</font><font color="#007700">(</font><font color="#0000BB">$obj</font><font color="#007700">);<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
><P
></P
></DIV
><P
>&#13;    Executing this example will result in the following output:
   </P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><PRE
CLASS="screen"
>NULL
object(stdClass)(0) {
}</PRE
></TD
></TR
></TABLE
><P
>&#13;    A similar behaviour applies to the <VAR
CLASS="literal"
>static</VAR
> statement.
    References are not stored statically:
   </P
><DIV
CLASS="informalexample"
><P
></P
><A
NAME="AEN1636"
></A
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><code><font color="#000000">
<font color="#0000BB">&lt;?php<br /></font><font color="#007700">function &amp;</font><font color="#0000BB">get_instance_ref</font><font color="#007700">() {<br />&nbsp;&nbsp;&nbsp;&nbsp;static </font><font color="#0000BB">$obj</font><font color="#007700">;<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#DD0000">"Static object: "</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">var_dump</font><font color="#007700">(</font><font color="#0000BB">$obj</font><font color="#007700">);<br />&nbsp;&nbsp;&nbsp;&nbsp;if (!isset(</font><font color="#0000BB">$obj</font><font color="#007700">)) {<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#FF8000">// Assign a reference to the static variable<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$obj </font><font color="#007700">= &amp;new </font><font color="#0000BB">stdclass</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;}<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$obj</font><font color="#007700">-&gt;</font><font color="#0000BB">property</font><font color="#007700">++;<br />&nbsp;&nbsp;&nbsp;&nbsp;return </font><font color="#0000BB">$obj</font><font color="#007700">;<br />}<br /><br />function &amp;</font><font color="#0000BB">get_instance_noref</font><font color="#007700">() {<br />&nbsp;&nbsp;&nbsp;&nbsp;static </font><font color="#0000BB">$obj</font><font color="#007700">;<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#DD0000">"Static object: "</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">var_dump</font><font color="#007700">(</font><font color="#0000BB">$obj</font><font color="#007700">);<br />&nbsp;&nbsp;&nbsp;&nbsp;if (!isset(</font><font color="#0000BB">$obj</font><font color="#007700">)) {<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#FF8000">// Assign the object to the static variable<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$obj </font><font color="#007700">= new </font><font color="#0000BB">stdclass</font><font color="#007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;}<br />&nbsp;&nbsp;&nbsp;&nbsp;</font><font color="#0000BB">$obj</font><font color="#007700">-&gt;</font><font color="#0000BB">property</font><font color="#007700">++;<br />&nbsp;&nbsp;&nbsp;&nbsp;return </font><font color="#0000BB">$obj</font><font color="#007700">;<br />}<br /><br /></font><font color="#0000BB">$obj1 </font><font color="#007700">= </font><font color="#0000BB">get_instance_ref</font><font color="#007700">();<br /></font><font color="#0000BB">$still_obj1 </font><font color="#007700">= </font><font color="#0000BB">get_instance_ref</font><font color="#007700">();<br />echo </font><font color="#DD0000">"\n"</font><font color="#007700">;<br /></font><font color="#0000BB">$obj2 </font><font color="#007700">= </font><font color="#0000BB">get_instance_noref</font><font color="#007700">();<br /></font><font color="#0000BB">$still_obj2 </font><font color="#007700">= </font><font color="#0000BB">get_instance_noref</font><font color="#007700">();<br /></font><font color="#0000BB">?&gt;</font>
</font>
</code></TD
></TR
></TABLE
><P
></P
></DIV
><P
>&#13;    Executing this example will result in the following output:
   </P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><PRE
CLASS="screen"
>Static object: NULL
Static object: NULL

Static object: NULL
Static object: object(stdClass)(1) {
  ["property"]=&#62;
  int(1)
}</PRE
></TD
></TR
></TABLE
><P
>&#13;    This example demonstrates that when assigning a reference to a static
    variable, it's not <SPAN
CLASS="emphasis"
><I
CLASS="emphasis"
>remembered</I
></SPAN
> when you call the
    <VAR
CLASS="literal"
>&#38;get_instance_ref()</VAR
> function a second time.
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