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<HTML
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>eval</TITLE
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><H1
><A
NAME="function.eval"
>eval</A
></H1
><DIV
CLASS="refnamediv"
><A
NAME="AEN22825"
></A
><P
>    (unknown)</P
>eval&nbsp;--&nbsp;Evaluate a string as PHP code</DIV
><DIV
CLASS="refsect1"
><A
NAME="AEN22828"
></A
><H2
>Description</H2
><DIV
CLASS="funcsynopsis"
><A
NAME="AEN22830"
></A
><P
></P
><P
><CODE
><CODE
CLASS="FUNCDEF"
>mixed <B
CLASS="function"
>eval</B
></CODE
> (string code_str)</CODE
></P
><P
></P
></DIV
><P
>&#13;     <B
CLASS="function"
>eval()</B
> evaluates the string given in
     <TT
CLASS="parameter"
><I
>code_str</I
></TT
> as PHP code. Among other things,
     this can be useful for storing code in a database text field for
     later execution.
    </P
><P
>&#13;     There are some factors to keep in mind when using
     <B
CLASS="function"
>eval()</B
>. Remember that the string passed must
     be valid PHP code, including things like terminating statements
     with a semicolon so the parser doesn't die on the line after the
     <B
CLASS="function"
>eval()</B
>, and properly escaping things in
     <TT
CLASS="parameter"
><I
>code_str</I
></TT
>.
    </P
><P
>&#13;     Also remember that variables given values under
     <B
CLASS="function"
>eval()</B
> will retain these values in the main
     script afterwards.
    </P
><P
>&#13;     A <TT
CLASS="literal"
>return</TT
> statement will terminate the evaluation of 
     the string immediatley. In PHP 4 you may use <TT
CLASS="literal"
>return</TT
>
     to return a value that will become the result of the 
     <B
CLASS="function"
>eval()</B
> function while in PHP 3 
     <B
CLASS="function"
>eval()</B
> was of type <TT
CLASS="literal"
>void</TT
> and did 
     never return anything.
    </P
><P
>&#13;     <TABLE
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><TR
><TD
><DIV
CLASS="example"
><A
NAME="AEN22852"
></A
><P
><B
>Example 1. 
       <B
CLASS="function"
>Eval()</B
> example - simple text merge
      </B
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="programlisting"
>&#13;&#60;?php
$string = 'cup';
$name = 'coffee';
$str = 'This is a $string with my $name in it.&#60;br&#62;';
echo $str;
eval ("\$str = \"$str\";");
echo $str;
?&#62;
      </PRE
></TD
></TR
></TABLE
></DIV
></TD
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>
    </P
><P
>&#13;     The above example will show:
     <TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="programlisting"
>&#13;This is a $string with my $name in it.
This is a cup with my coffee in it.
     </PRE
></TD
></TR
></TABLE
>
    </P
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