尝试对xml文件进行迭代，以匹配用于登录的xml文件的结果

我有两个xml文件，多亏了Lawrance，我能够将登录用户的xml详细信息解析到admin_panel，现在我正试图迭代第二个xml文件（该文件仅共享unique_ref作为参考），因为我是PHP和xml的新手，我正在努力获得我想要的结果。xml中的日志是

<MYData>
    <login_details>
        <unique_ref>1-61</unique_ref>
        <login_name>tomme</login_name>
        <login>me</login>
        <password>me</password>
        <file1>Test</file1>
        <file2/>
        <file3/>
        <file4/>
    </login_details>
    <login_details>
        <unique_ref>1-63</unique_ref>
        <login_name>tony</login_name>
        <login>tony</login>
        <password>tony</password>
        <file1>Test1</file1>
        <file2/>
        <file3/>
        <file4/>
    </login_details>
</MYData> 

以及用户图像的第二个xml文件

<MYData>
<mydata_images>
<unique_ref>1-61</unique_ref>
 <image1>IMG_0125.JPG</image1>
 <image2>IMG_0122.JPG</image2>
 <stat_date>2013-02-03</stat_date>
 <path_file>C:'DATA''documents'page_1.pdf</path_file>
</mydata_images>
<mydata_images>
<unique_ref>1-61</unique_ref>
 <image1>IMG_0127.JPG</image1>
 <image2>IMG_0128.JPG</image2>
 <stat_date>2013-04-03</stat_date>
 <path_file>C:'DATA''documents'page_3.pdf</path_file>
</mydata_images>
<mydata_images>
<unique_ref>1-63</unique_ref>
 <image1>2.THEMOUNT.JPG</image1>
 <image2>1.THE-MOUNT.JPG</image2>
 <stat_date>2013-01-03</stat_date>
 <path_file>C:'DATA''documents'page_2.pdf</path_file>
</mydata_images>
<mydata_images>
<unique_ref>1-61</unique_ref>
  <image1>IMG_0109.JPG</image1>
  <image2>IMG_0112.JPG</image2>
 <stat_date>2013-05-03</stat_date>
 <path_file>C:'DATA''documents'page_4.pdf</path_file>
</mydata_images>
</MYData>

我想显示登录用户的图像和我尝试过的array_incross的pdf，但我一直收到一个错误，这是我一直在玩的admin_panel

<?php
session_start();
//logout
$mydata2 = simplexml_load_file("xml/mydata_images.xml");
if(isset($_GET['logout'])){unset($_SESSION['logged_in']);session_destroy();}

//check login
if(isset($_SESSION['logged_in']) && $_SESSION['logged_in']==true){
    //json decode user details from session into an array
    $user_details = json_decode($_SESSION['user_details'],true);
    $id = json_decode($_SESSION['id'],true);
    //debug your values
    $unique_ref =$mydata2->mydata_images;
    echo $unique_ref;
    $result = array_intersect($user_details,$unique_ref );
    $unique_ref =$user_details["unique_ref"];
    //foreach ($mydata2 as $unique_ref => $result){
        //print "$unique_ref = $result'n";
       // print_r($result);
    //}
    echo '<pre>'.print_r($user_details,true).'</pre>';
    echo $id;
    echo $user_details["login"];
    echo $unique_ref;
    echo $result;
    /*
    Array
    (
        [unique_ref] => 1-61
        [login_name] => tomme
        [login] => me
        [file1] => Test
        [file2] => Array
            (
            )
        [file3] => Array
            (
            )
        [file4] => Array
            (
            )
    )
    */
    echo '<a href="?logout">logout</a>';
}else{
    exit(header("Location: ./login.php"));
}
?>