Namespaces and dynamic language features
(PHP 5 >= 5.3.0, PHP 7)
PHP's implementation of namespaces is influenced by its dynamic nature as a programming language. Thus, to convert code like the following example into namespaced code:
Example #1 Dynamically accessing elements
example1.php:
<?php
class?classname
{
????function?__construct()
????{
????????echo?__METHOD__,"\n";
????}
}
function?funcname()
{
????echo?__FUNCTION__,"\n";
}
const?constname?=?"global";
$a?=?'classname';
$obj?=?new?$a;?//?prints?classname::__construct
$b?=?'funcname';
$b();?//?prints?funcname
echo?constant('constname'),?"\n";?//?prints?global
?>One must use the fully qualified name (class name with namespace prefix). Note that because there is no difference between a qualified and a fully qualified Name inside a dynamic class name, function name, or constant name, the leading backslash is not necessary.
Example #2 Dynamically accessing namespaced elements
<?php
namespace?namespacename;
class?classname
{
????function?__construct()
????{
????????echo?__METHOD__,"\n";
????}
}
function?funcname()
{
????echo?__FUNCTION__,"\n";
}
const?constname?=?"namespaced";
/*?note?that?if?using?double?quotes,?"\\namespacename\\classname"?must?be?used?*/
$a?=?'\namespacename\classname';
$obj?=?new?$a;?//?prints?namespacename\classname::__construct
$a?=?'namespacename\classname';
$obj?=?new?$a;?//?also?prints?namespacename\classname::__construct
$b?=?'namespacename\funcname';
$b();?//?prints?namespacename\funcname
$b?=?'\namespacename\funcname';
$b();?//?also?prints?namespacename\funcname
echo?constant('\namespacename\constname'),?"\n";?//?prints?namespaced
echo?constant('namespacename\constname'),?"\n";?//?also?prints?namespaced
?>Be sure to read the note about escaping namespace names in strings.
← Using namespaces: Basics
namespace keyword and __NAMESPACE__ constant →
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