我们在通过学习VideoCard.php 接口文件（显卡的功能接口定义）
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<li class="alt"><span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">php</span></font></strong><span> </span></span></li>
<li class=""><span>interface VideoCardInter{ </span></li>
<li class="alt"><span> function Display(); </span></li>
<li class=""><span> function getName(); </span></li>
<li class="alt"><span>} </span></li>
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<span></span><span class="tag"><strong><font color="#006699">?></font></strong></span><span> </span>
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</ol>Dmeng.php 实现接口（帝盟的厂家实现了这些接口，怎么实现的，主板厂家不用管）
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<li class="alt"><span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">php</span></font></strong><span> </span></span></li>
<li class=""><span>include_once("VideoCard.php"); </span></li>
<li class="alt"><span>class Dmeng implements VideoCardInter { </span></li>
<li class=""><span> function Display(){ </span></li>
<li class="alt"><span> echo "Display"; </span></li>
<li class=""><span> } </span></li>
<li class="alt"><span> function getName(){ </span></li>
<li class=""><span> return "Dmeng VideoCard"; </span></li>
<li class="alt"><span> } </span></li>
<li class=""><span>} </span></li>
<li class="alt">
<span></span><span class="tag"><strong><font color="#006699">?></font></strong></span><span> </span>
</li>
</ol>Mainboard.php 应用接口（把显卡插到主板上，主板只要用这些接口就行了，也可以不用）
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<li class="alt"><span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">php</span></font></strong><span> </span></span></li>
<li class=""><span>include_once("VideoCard.php"); </span></li>
<li class="alt"><span>include_once("Dmeng.php"); </span></li>
<li class=""><span>class Mainboard{ </span></li>
<li class="alt"><span> var $vc; </span></li>
<li class=""><span> function run(VideoCardInter $vc){ //定义VideoCardInter接口类型参数，这时并不知道是谁来实现。 </span></li>
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<span> $this-</span><span class="tag"><strong><font color="#006699">></font></strong></span><span class="attribute"><font color="#ff0000">vc</font></span><span>=$vc; </span>
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<span> $this-</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>vc-</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>Display(); </span>
</li>
<li class="alt"><span> echo "主板运行！"; </span></li>
<li class=""><span> } </span></li>
<li class="alt"><span>} </span></li>
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<span>$</span><span class="attribute"><font color="#ff0000">conputer</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">new</font></span><span> Mainboard(); </span>
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<li class="alt">
<span>$conputer-</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>run(new Dmeng); //用的时候把实现接口类的名称写进来，<br>（现在是帝盟的显卡，也可以换成别的场家的，只要他们都实现了接口） </span>
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<span></span><span class="tag"><strong><font color="#006699">?></font></strong></span><span> </span>
</li>
</ol>由于PHP是动态语言，所以类型不能像JAVA一样定的很死，定义接口的时候，写上返回类型反而出错，估计PHP6的时候可能写义的要严格一些吧。
PS:我只把PHP接口特性最基本的部分写上，还可以加CPU等接口。
