Defining multiple namespaces in the same file
(PHP 5 >= 5.3.0, PHP 7)
Multiple namespaces may also be declared in the same file. There are two allowed syntaxes.
Example #1 Declaring multiple namespaces, simple combination syntax
<?php
namespace?MyProject;
const?CONNECT_OK?=?1;
class?Connection?{?/*?...?*/?}
function?connect()?{?/*?...?*/??}
namespace?AnotherProject;
const?CONNECT_OK?=?1;
class?Connection?{?/*?...?*/?}
function?connect()?{?/*?...?*/??}
?>This syntax is not recommended for combining namespaces into a single file. Instead it is recommended to use the alternate bracketed syntax.
Example #2 Declaring multiple namespaces, bracketed syntax
<?php
namespace?MyProject?{
const?CONNECT_OK?=?1;
class?Connection?{?/*?...?*/?}
function?connect()?{?/*?...?*/??}
}
namespace?AnotherProject?{
const?CONNECT_OK?=?1;
class?Connection?{?/*?...?*/?}
function?connect()?{?/*?...?*/??}
}
?>It is strongly discouraged as a coding practice to combine multiple namespaces into the same file. The primary use case is to combine multiple PHP scripts into the same file.
To combine global non-namespaced code with namespaced code, only bracketed syntax is supported. Global code should be encased in a namespace statement with no namespace name as in:
Example #3 Declaring multiple namespaces and unnamespaced code
<?php
namespace?MyProject?{
const?CONNECT_OK?=?1;
class?Connection?{?/*?...?*/?}
function?connect()?{?/*?...?*/??}
}
namespace?{?//?global?code
session_start();
$a?=?MyProject\connect();
echo?MyProject\Connection::start();
}
?>No PHP code may exist outside of the namespace brackets except for an opening declare statement.
Example #4 Declaring multiple namespaces and unnamespaced code
<?php
declare(encoding='UTF-8');
namespace?MyProject?{
const?CONNECT_OK?=?1;
class?Connection?{?/*?...?*/?}
function?connect()?{?/*?...?*/??}
}
namespace?{?//?global?code
session_start();
$a?=?MyProject\connect();
echo?MyProject\Connection::start();
}
?>← Declaring sub-namespaces
Using namespaces: Basics →
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