自引用XML树以创建多层无序列表

时间:2012-08-08 20:49:00

标签: php xml recursion

我的目标是创建具有无限深度树的导航菜单。我可以成功生成前2个级别。第一个(顶级)使用的是未存储在XML文件中的PHP数组。第二个是从平面xml文件生成的。主要问题是成功的递归。

这是XML结构:

<articles>
    <article>
        <menu parent="Insurance" label="Business" target="#" show="true" />
        <data />
        <body />
    </article>
    <article>
        <menu parent="Resources" label="Videos" target="content.php#videos" show="true" />
        <data />
        <body />
    </article>
    <article>
        <menu parent="Business" label="Disability" target="content.php#disability" show="true" />
        <data />
        <body />
    </article>
    <article>
        <menu parent="Business" label="Liability" target="content.php#liability" show="true" />
        <data />
        <body />
    </article>

</articles>

我在目标属性中使用#来确定是否需要启动新列表(子菜单)。

我通过输出正确信息获得成功的PHP代码是:

    $objXMLMenu = simplexml_load_file('menu.xml');
    foreach ($mainmenu as $menuparent) {  //Main Array

        echo "<li><a href=\"" .$maintargets[$i]. "\">". $menuparent ."</a>\n";  // Top Menu array. I use 2 for clarity
        if ($maintargets[$i] == "#"){


            //Open the ULs for filling
            echo "\t<ul>\n";

    // Start function here?

            foreach($objXMLMenu->article as $art){

                foreach($art->menu as $menuitem){

                    if($menuitem['parent'] == $menuparent){ //Compare to Main Array

                        if ($menuitem['show'] == "true"){

                            if($menuitem['target'] == "#"){  //A Submenu exits here
                                echo "\t\t<li><a href=\"" . $menuitem['target'] . "\" >" .$menuitem['label'] . "</a></li>\n";
                                echo "\t\t\t<ul>\n";
                                //Run XMLQUERY match? As a 

                                echo "\t\t\t</ul>\n";
                            }else{
                                echo "\t\t<li><a href=\"" . $menuitem['target'] . " \"rel=\"ajax\">" .$menuitem['label'] . "</a></li>\n";
                            }
                        }

                    }
                }

            }
            //Close Middle Menus
            echo "\t</ul>";
        }
        $i++;
        //close Top Level Menu Item
        echo "</li>\n";
    }
//<UL> Footer
echo "\t</ul>\n</div>\n";

为了使它成为一个递归函数,我收到了第一个foreach语句的错误,这表明我应该切换到DOM&amp; XPATH而不是simplexml。这是我到目前为止所提出的功能:

$objXMLMenu = simplexml_load_file('menu.xml');
// Start function here!
function mysubmenu($menuparent){
    foreach($objXMLMenu->article as $art){
        foreach($art->menu as $menuitem){
            if($menuitem['label'] == $menuparent){
            //Compare to Main Array
                if ($menuitem['show'] == "true"){

                    if($menuitem['target'] == "#"){
                        // ((ROOT)
                        //A Submenu exits here
                        $strResponse .= "\t\t<li><a href=\"" . $menuitem['target'] . " \">" .$menuitem['label'] . "</a></li>\n";
                        $strResponse .= "\t\t\t<ul>\n";

                        //xmlpath QUERY instead?
                        mysubmenu($menuitem['parent']);

                        $strResponse .= "\t\t\t</ul>\n";
                    }else{
                        $strResponse .= "\t\t<li><a href=\"" . $menuitem['target'] . " \"rel=\"ajax\">" .$menuitem['label'] . "</a></li>\n";
                    }
                }

            }
        }
        //insert counter to stop foreach loop after all records are posted.
    }
    return $strResponse; 
} //End Function

这种类型的递归对我来说是一个新的界限。我发现的每个例子或解释都涉及到XML树更深入到元素中。 “深度”(计数器)属性不是一个选项。因为,我在一个“推迟”的项目中面临着类似的问题,这个项目确实是一段时间内无限的深度。

1 个答案:

答案 0 :(得分:0)

在程序样式上工作的东西在函数中不起作用。我最令人不安的方面是comparing SimpleXML objects。大约有5行需要更改。对于更长的递归,可能有一种更简单,更快速的方法来获得这个答案。但我发现这个目前有效。

function mysubmenu($menuparent){
    $objXMLMenu = simplexml_load_file('menu.xml');
    foreach($objXMLMenu->article as $art){
        foreach($art->menu as $menuitem){

            if((string)$menuitem['parent'] == $menuparent){ 
                if ($menuitem['show'] == "true"){
                    if($menuitem['target'] == "#"){
                        echo "\t\t<li><a href=\"" . $menuitem['target'] . "\">" .$menuitem['label'] . "</a></li>\n";
                        echo "\t\t\t<ul>\n";
                        mysubmenu($menuitem['label']);
                        echo "\t\t\t</ul>\n";
                    }else{
                        echo "\t\t<li><a href=\"" . $menuitem['target'] . "\" rel=\"ajax\">" .$menuitem['label'] . "</a></li>\n";
                    }
                }


            }
        }

    }

} //End Function