Strategy pattern:
Encapsulate a specific set of behaviors and algorithms into classes to adapt to certain specific contexts;
A practical application example, if an e-commerce website system requires male and female users to jump to different product categories, and all advertising slots display different ads.
UserStrategy.php
<?<span>php namespace Baobab; </span><span>interface</span><span> UserStrategy{ </span><span>function</span><span> showAd(); </span><span>function</span><span> showCategory(); } </span>?>
FemaleUserStrategy.php
<?<span>php namespace Baobab; </span><span>class</span> FemaleUserStrategy <span>implements</span><span> UserStrategy{ </span><span>function</span><span> showAd(){ </span><span>echo</span> '2016新款女装'<span>; } </span><span>function</span><span> showCategory(){ </span><span>echo</span> '女装'<span>; } } </span>?>
MaleUserStrategy.php
<?<span>php namespace Baobab; </span><span>class</span> MaleUserStrategy <span>implements</span><span> UserStrategy{ </span><span>function</span><span> showAd(){ </span><span>echo</span> 'Iphone6s plus'<span>; } </span><span>function</span><span> showCategory(){ </span><span>echo</span> '电子产品'<span>; } } </span>?>
Page.php
<span><span>namespace Baobab;</span><br>class</span><span> Page{ </span><span>protected</span><span>$strategy</span><span>; </span><span>function</span><span> Index(){ </span><span>$this</span>->strategy-><span>showAd(); </span><span>echo</span> '<br/>'<span>; </span><span>$this</span>->strategy-><span>showCategory(); } </span><span>function</span> setStrategy(\Baobab\UserStrategy <span>$strategy</span><span>){ </span><span>$this</span>->strategy = <span>$strategy</span><span>; } } </span>
index.php
<span>$page</span> = <span>new</span><span> Baobab\Page(); </span><span>if</span> (<span>isset</span>(<span>$_GET</span>['female'<span>])){ </span><span>$strategy</span> = <span>new</span><span> Baobab\FemaleUserStrategy(); }</span><span>else</span><span>{ </span><span>$strategy</span> = <span>new</span><span> Baobab\MaleUserStrategy(); } </span><span>$page</span>->setStrategy(<span>$strategy</span><span>); </span><span>$page</span>->Index();
Use strategy pattern to implement IOC and dependency Inversion, inversion of control
The above introduces the PHP design pattern and strategy pattern, including aspects of the content. I hope it will be helpful to friends who are interested in PHP tutorials.