PHP实现无级递归分门别类（ThinkPHP框架）

<span style="color: #008000;">/*</span><span style="color: #008000;">**   无级递归分类*   @param   int     $assortPid   要查询分类的父级id*   @param   mixed   $tag         上下级分类之间的分隔符*   @return  string  $tree        返回的分类树型结构结果 *</span><span style="color: #008000;">*/</span><span style="color: #0000ff;">function</span> recursiveAssort(<span style="color: #800080;">$assortPid</span>, <span style="color: #800080;">$tag</span> = ''<span style="color: #000000;">){       </span><span style="color: #800080;">$assort</span> = M('goods_class')->where("class_pid = <span style="color: #800080;">$assortPid</span>")->field('class_id, class_name')-><span style="color: #000000;">select();    </span><span style="color: #0000ff;">foreach</span> (<span style="color: #800080;">$assort</span> <span style="color: #0000ff;">as</span> <span style="color: #800080;">$value</span><span style="color: #000000;">) {        </span><span style="color: #800080;">$tree</span> .= '<option value="' . <span style="color: #800080;">$value</span>['class_id'] . '">' . <span style="color: #800080;">$tag</span> . <span style="color: #800080;">$value</span>['class_name'] . '</option>'<span style="color: #000000;">;        </span><span style="color: #800080;">$tree</span> .= recursiveAssort(<span style="color: #800080;">$value</span>['class_id'], <span style="color: #800080;">$tag</span> . '&emsp;'<span style="color: #000000;">);    }    </span><span style="color: #0000ff;">return</span> <span style="color: #800080;">$tree</span><span style="color: #000000;">;}</span>