手把手教你做关键词匹配项目（搜索引擎）---- 第十八天，教你做第十八天

手把手教你做关键词匹配项目（搜索引擎）---- 第十八天，教你做第十八天

第十八天

客串：屌丝的坑人表单神器

走过的那些事儿：数据库那点事儿

起点：手把手教你做关键词匹配项目（搜索引擎）---- 第一天

回顾：手把手教你做关键词匹配项目（搜索引擎）---- 第十七天

上回说到小帅帅把代码交给于老大时，于老大批了小帅帅，小帅帅真的感觉受委屈了。

我们回到站在技术总监的角度看问题，技术总监真的要做到监管代码的可读行吗？

我记得很多公司都是提倡利益，利益作为衡量一个技术总监的价值。

技术总监做错了吗？超出他的职责范围了吗？

其实于老大看到 LinklistCharListHandle类里面exec方法出现了三层foreach，就把小帅帅给批了。

好严格的于老大，还是于老大对小帅帅的期望比较高。

小帅帅没办法，他只好把foreach尽量提取出来，小帅帅的版本：

<span>class</span> LinklistCharListHandle <span>extends</span><span> CharListHandle {
    </span><span>public</span> <span>function</span> <span>exec</span><span>(){
        </span><span>$sql</span> = "select word from category_linklist where cid='<span>$this</span>->selectorItem->cid'"<span>;
        </span><span>$linklist</span> = DB::makeArray(<span>$sql</span><span>);
        </span><span>foreach</span>(<span>$linklist</span> <span>as</span> <span>$strWords</span><span>){
            </span><span>$words</span> = <span>explode</span>(",",<span>$strWords</span><span>);

            </span><span>$this</span>->propertiesTransferCharlist(<span>$words</span><span>);

        }
    }

    </span><span>public</span> <span>function</span> propertiesTransferCharlist(<span>$linkWords</span><span>){
        </span><span>$properties</span> = <span>$this</span>->selectorItem-><span>getProperties();
        </span><span>foreach</span>(<span>$properties</span> <span>as</span> <span>$property</span><span>){

            </span><span>$this</span>->charlist->addCore(<span>$property</span>-><span>value);
            </span><span>if</span>(<span>in_array</span>(<span>$property</span>->value,<span>$linkWords</span><span>)){
                </span><span>$this</span>->addCores(<span>$linkWords</span><span>);
            }
        }
    }

    </span><span>public</span> <span>function</span> addCores(<span>$words</span><span>){
        </span><span>foreach</span>(<span>$words</span> <span>as</span> <span>$char</span><span>){
            </span><span>$this</span>->charlist->addCore(<span>$char</span><span>);
        }
    }
}</span>

小帅帅提取了两个方法，使程序更加能够看懂了。

其实小帅帅的的做法就是使用重构-改善既有代码的设计的技巧之一，Extract Method 提炼函数

Extract Method：将这段代码放进一个独立函数中，并让函数名称解析该函数的用途。

小帅帅很有成就感，继续把代码给于老大的时候，于老大提到了两点。

1. propertiesTransferCharlist为什么要接受个参数。<br />2. addCores到底是那个类的职责范围。<br /><br /><br />

小帅帅第2种他知道怎么做，他把该方法移到Charlist类里面，代码如下：

<?<span>php
</span><span>class</span><span> CharList {

    </span><span>private</span> <span>$core</span> = <span>array</span><span>();
    </span><span>private</span> <span>$blacklist</span> = <span>array</span><span>();

    </span><span>public</span> <span>function</span> addCore(<span>$char</span><span>){
        </span><span>if</span>(!<span>in_array</span>(<span>$char</span>,<span>$this</span>-><span>core))
            </span><span>$this</span>->core[] = <span>$char</span><span>;
    }
    
    </span><span>public</span> <span>function</span> addCores(<span>$words</span><span>){
        </span><span>foreach</span>(<span>$words</span> <span>as</span> <span>$char</span><span>){
            </span><span>$this</span>->addCore(<span>$char</span><span>);
        }
    }

    </span><span>public</span> <span>function</span><span> getCore(){
        </span><span>return</span> <span>$this</span>-><span>core;
    }

    </span><span>public</span> <span>function</span> addBlacklist(<span>$char</span><span>){
        </span><span>if</span>(!<span>in_array</span>(<span>$char</span>,<span>$this</span>-><span>blacklist))
            </span><span>$this</span>->blacklist[] = <span>$char</span><span>;
    }

    </span><span>public</span> <span>function</span><span> getBlacklist(){
        </span><span>return</span> <span>$this</span>-><span>blacklist;
    }
}</span>

其实小帅帅的这次做法还是使用重构-改善既有代码的设计的技巧之一，Move Method 搬移函数。

Move Method：在该函数最常引用的类中建立一个有着类似行为的新函数。将旧函数变成一个单纯的委托函数，或是将旧函数完全移除。

小帅实在搞不懂第1个怎么办，又去请教于老大，于老大直接把代码给了小帅帅，于老大的代码为：

<?<span>php
</span><span>class</span> LinklistCharListHandle <span>extends</span><span> CharListHandle {
    
    </span><span>private</span> <span>static</span> <span>$linklist</span><span>; 
    
    </span><span>public</span> <span>function</span> <span>exec</span><span>(){
       </span><span>$this</span>-><span>propertiesTransferCharlist();
    }
    
    </span><span>public</span> <span>static</span> <span>function</span> linklist(<span>$cid</span><span>){
        </span><span>if</span>(!<span>isset</span>(self::<span>$linklist</span>) || !<span>isset</span>(self::<span>$linklist</span>[<span>$cid</span>]) || self::<span>$linklist</span>[<span>$cid</span>] == <span>null</span><span>){
            </span><span>$sql</span> = "select word from category_linklist where cid='<span>$cid</span>'"<span>;
            self</span>::<span>$linklist</span>[<span>$cid</span>] = DB::makeArray(<span>$sql</span><span>);
        }
        </span><span>return</span> self::<span>$linklist</span>[<span>$cid</span><span>];
    }

    </span><span>public</span> <span>function</span><span> propertiesTransferCharlist(){
        </span><span>$properties</span> = <span>$this</span>->selectorItem-><span>getProperties();
        </span><span>foreach</span>(<span>$properties</span> <span>as</span> <span>$property</span><span>){
            
            </span><span>$this</span>->charlist->addCore(<span>$property</span>-><span>value);            
            </span><span>$this</span>->extendCharlist(<span>$property</span>-><span>value);           
        }
    }
    
    </span><span>public</span> <span>function</span> extendCharlist(<span>$char</span><span>){
        </span><span>$linklist</span> = self::linklist(<span>$this</span>->selectorItem-><span>cid);
        </span><span>foreach</span>(<span>$linklist</span> <span>as</span> <span>$strWords</span><span>){
            </span><span>$words</span> = <span>explode</span>(",",<span>$strWords</span><span>);
            </span><span>if</span>(<span>in_array</span>(<span>$char</span>,<span>$words</span><span>)){
                </span><span>$this</span>->charlist->addCores(<span>$words</span><span>);
            }
        }
        
    }    
}</span>

小帅帅看了，发表了一次感叹，原来代码随便改变下，区别这么大，以前为啥从来没有这感觉。

 

小帅帅真希望自己能够独单一面，不用天天去找于老大。