Sophie: php-manual-en-4.3.0-2mdk noarch

php-manual-en-4.3.0-2mdk.noarch.rpm

<HTML
><HEAD
><TITLE
>Assignment Operators</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
REL="HOME"
TITLE="PHP Manual"
HREF="index.html"><LINK
REL="UP"
TITLE="Operators"
HREF="language.operators.html"><LINK
REL="PREVIOUS"
TITLE="Arithmetic Operators"
HREF="language.operators.arithmetic.html"><LINK
REL="NEXT"
TITLE="Bitwise Operators"
HREF="language.operators.bitwise.html"><META
HTTP-EQUIV="Content-type"
CONTENT="text/html; charset=ISO-8859-1"></HEAD
><BODY
CLASS="sect1"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
SUMMARY="Header navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>PHP Manual</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="language.operators.arithmetic.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
>Chapter 11. Operators</TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="language.operators.bitwise.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="sect1"
><H1
CLASS="sect1"
><A
NAME="language.operators.assignment"
></A
>Assignment Operators</H1
><P
>&#13;    The basic assignment operator is "=". Your first inclination might
    be to think of this as "equal to". Don't. It really means that the
    the left operand gets set to the value of the expression on the
    rights (that is, "gets set to").
   </P
><P
>&#13;    The value of an assignment expression is the value assigned. That
    is, the value of "$a = 3" is 3. This allows you to do some tricky
    things: 
    <DIV
CLASS="informalexample"
><A
NAME="AEN4508"
></A
><P
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><PRE
CLASS="php"
>$a = ($b = 4) + 5; // $a is equal to 9 now, and $b has been set to 4.</PRE
></TD
></TR
></TABLE
><P
></P
></DIV
>
   </P
><P
>&#13;    In addition to the basic assignment operator, there are "combined
    operators" for all of the binary arithmetic and string operators
    that allow you to use a value in an expression and then set its
    value to the result of that expression. For example:
    <DIV
CLASS="informalexample"
><A
NAME="AEN4511"
></A
><P
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
CELLPADDING="5"
><TR
><TD
><PRE
CLASS="php"
>$a = 3;
$a += 5; // sets $a to 8, as if we had said: $a = $a + 5;
$b = "Hello ";
$b .= "There!"; // sets $b to "Hello There!", just like $b = $b . "There!";</PRE
></TD
></TR
></TABLE
><P
></P
></DIV
>
   </P
><P
>&#13;    Note that the assignment copies the original variable to the new
    one (assignment by value), so changes to one will not affect the
    other. This may also have relevance if you need to copy something
    like a large array inside a tight loop. PHP 4 supports assignment
    by reference, using the <TT
CLASS="computeroutput"
>$var =
    &#38;$othervar;</TT
> syntax, but this is not possible
    in PHP 3. 'Assignment by reference' means that both variables end
    up pointing at the same data, and nothing is copied anywhere. 
    To learn more about references, please read <A
HREF="language.references.html"
>References explained</A
>.
   </P
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
SUMMARY="Footer navigation table"
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="language.operators.arithmetic.html"
ACCESSKEY="P"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="index.html"
ACCESSKEY="H"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="language.operators.bitwise.html"
ACCESSKEY="N"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
>Arithmetic Operators</TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="language.operators.html"
ACCESSKEY="U"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
>Bitwise Operators</TD
></TR
></TABLE
></DIV
></BODY
></HTML
>