XML搜索和addChild

Question

這是我到目前爲止，我想添加日期/時間日誌到XML文件。

<?php 

     // Load the XML file we want to write to 
      $visitors = simplexml_load_file("data.xml"); 

     // Set e-mail xml search 
      $search_id = htmlentities($_POST['email']); 
      $visitors = $visitors->xpath("visitor[email='$search_id']"); 

     // If we have a search result, email already exists in xml file 
      if(isset($visitors[0])){ 
      $visitor = $visitors[0]; 
      $email = (string) $visitor->email; 

      // ********** Need to add date/time for each visit here. 
      // So, I guess I need to search for e-mail address, then append to it. 
      // Help required here... and again below to confirm formatting for multiple 
      // dates. 

      } else { 
      $xml = simplexml_load_file("data.xml"); 
      $sxe = new SimpleXMLElement($xml->asXML()); 
      $search_id = preg_replace('/[^(\x20-\x7F)]*/','', $search_id); 

      $visitor = $sxe->addChild("visitor"); 
      $visitor->addChild("email", $search_id); 

      // ******** Not sure this is the correct xml formatting. 
       $date = $visitor->addChild('date'); 
       $date->addChild("email", date("Y-m-d H:i:s")); 

      $sxe->asXML("data.xml"); 
      } // if(isset($visitors[0])){ 

     } // if(isset($data)){ ?> 

產生

<?xml version="1.0" encoding="utf-8"?> 
<visitors> 
<visitor> 
    <email>jon.doe@aol.com</email> 
    </visitor> 
</visitors> 

我想要做的就是添加日期日誌（incementing /追加），每次訪問。

所以結果會是（我不確定我的格式是否正確，哪些當然不起作用）。不要擔心日期/時間的PHP。

<?xml version="1.0" encoding="utf-8"?> 
<visitors> 
<visitor> 
    <email>jon.doe@aol.com</email> 
    <date>2012-11-01 11:00:00</date> 
    <date>2012-11-02 14:00:00</date> 
    </visitor> 
</visitors> 

Answer 1

這是一個除了@Geekmans answer

您的代碼不看遠的。然而，你可以大大改善它，這就是爲什麼在這裏添加另一個答案（我通常會編輯@Geekmans回答，但它已經非常大）。

改進的地方在於程序流程。如果找不到電子郵件，則不需要創建新的SimpleXMLElement，只需創建新的<visitor>元素。然後添加<date>元素以及輸出文件對於這兩種情況實際上是相同的。這允許刪除重複的代碼：

// Specify the XML file we want to write to 
$inFile = "data.xml"; 

// Set e-mail xml search and insert id 
$search_id = 'jon.doe@aol.com'; 
$insert_id = preg_replace('/[^(\x20-\x7F)]*/', '', $search_id); 

// Load the XML file we want to write to 
$xmlFile = simplexml_load_file($inFile); 
$results = $xmlFile->xpath("visitor[email='$search_id']"); 

// If we have a search result, email already exists in xml file 
if ($results) { 
    $visitor = $results[0]; 
    echo "Found Visitor: ", $visitor->email, "\n", 
    "First Date: ", $visitor->date, "\n"; 
} else { 
    echo "Adding new Visitor: ", $insert_id, "\n"; 
    $visitor = $xmlFile->addChild("visitor"); 
    $visitor->addChild("email", $insert_id); 
} 

echo "Adding new Date: ", $date = date('Y-m-d H:i:s'), "\n"; 
$visitor->addChild('date', $date); 

echo "Changed XML: \n" . simplexml_pretty_print($xmlFile); 
$xmlFile->asXML($inFile); 


/** 
* @param SimpleXMLElement $simplexml 
* @link https://stackoverflow.com/a/798986/367456 
*/ 
function simplexml_pretty_print(SimpleXMLElement $simplexml) { 
    $dom      = new DOMDocument(); 
    $dom->preserveWhiteSpace = false; 
    $dom->formatOutput  = true; 
    $dom->loadXML($simplexml->asXML()); 
    return $dom->saveXML(); 
} 

當我加入了simplexml_pretty_print功能有一個更好的方式輸出的獎金。

爲jon.doe@aol.com輸出：

Found Visitor: jon.doe@aol.com 
First Date: 2012-11-01 11:00:00 
Adding new Date: 2012-11-03 10:48:05 
Changed XML: 
<?xml version="1.0" encoding="utf-8"?> 
<visitors> 
    <visitor> 
    <email>jon.doe@aol.com</email> 
    <date>2012-11-01 11:00:00</date> 
    <date>2012-11-02 14:00:00</date> 
    <date>2012-11-03 10:48:05</date> 
    </visitor> 
</visitors> 

爲info@example.com輸出：

Adding new Visitor: info@example.com 
Adding new Date: 2012-11-03 10:52:09 
Changed XML: 
<?xml version="1.0" encoding="utf-8"?> 
<visitors> 
    <visitor> 
    <email>jon.doe@aol.com</email> 
    <date>2012-11-01 11:00:00</date> 
    <date>2012-11-02 14:00:00</date> 
    </visitor> 
    <visitor> 
    <email>info@example.com</email> 
    <date>2012-11-03 10:52:09</date> 
    </visitor> 
</visitors> 

提示：當你發現重複的代碼，往往是把它寫在一個更簡單的方式形成。

Answer 2

我覺得你在這裏在正確的軌道上，更主要的是，你對asXML通話（「data.xml中」）是你的ELSE塊內，所以文件只被寫入到文件，如果它是從頭開始創建（即沒有找到search_id）。

我做了一些改動，主要是爲了讓它更容易遵循。更多的變化來!:

<?php 

// Load the XML file we want to write to 
$xmlFile = simplexml_load_file("data.xml"); 

// Set e-mail xml search 
$search_id = 'jon.doe@aol.com'; 
$results = $xmlFile->xpath("visitor[email='$search_id']"); 

// If we have a search result, email already exists in xml file 
if(isset($results[0])) 
{ 
    $visitor = $results[0]; 
    $email = (string) $visitor->email; 

    echo "Found Email: " . $email . "\n"; 
    echo "Date: " . $visitor->date . "\n"; 
    // ********** Need to add date/time for each visit here. 
    // So, I guess I need to search for e-mail address, then append to it. 
    // Help required here... and again below to confirm formatting for multiple 
    // dates. 
    echo "Adding new date"; 
    $visitor->addChild('date', date('Y-m-d H:i:s')); 

    echo "New XML: " . $xmlFile->asXML(); 

    $xmlFile->asXML('data.xml'); 

} else { 
    $sxe = new SimpleXMLElement($xmlFile->asXML()); 
    $search_id = preg_replace('/[^(\x20-\x7F)]*/','', $search_id); 

    $visitor = $sxe->addChild("visitor"); 
    $visitor->addChild("email", $search_id); 

    // ******** Not sure this is the correct xml formatting. 
    $date = $visitor->addChild('date', date('Y-m-d H:i:s')); 

    $sxe->asXML("data.xml"); 

} 
?> 

運行此腳本了幾次後，我得到了：

<?xml version="1.0"?> 
<visitors> 
     <visitor> 
       <email>jon.doe@aol.com</email> 
       <date>2012-11-03 02:13:28</date> 
       <date>2012-11-03 02:20:20</date> 
       <date>2012-11-03 02:22:07</date> 
       <date>2012-11-03 02:22:10</date> 
       <date>2012-11-03 02:22:13</date> 
     </visitor> 
</visitors> 

我認爲這是你想要的嗎？這有幫助嗎？

編輯：

關於你的它是否是正確的XML格式提。我想沒有專有的正確答案。我會說這種格式沒有問題，只要你記得在自己的訪問者標籤中分隔每個單獨的電子郵件地址/一組日期。

要做到這一點，你可能想要的東西，像這樣（未經）：

$newVisitor = $xmlFile->addChild('visitor'); 
$newVisitor->addChild('email', $newEmail); 
$newVisotor->addChild('date', $newDate); 
$xmlFile->asXML('data.xml'); 

編輯2：

，我已經在過去使用

最後一件事是以下碼。它將格式化XML更好，並且還可以防止原始XML文件的任何損壞，如果您在保存期間有任何問題（或至少會給您一個備份）。就我個人而言，我試圖習慣於在任何時候需要寫入文件時使用這樣的臨時文件。

當然，只是添加這個，然後更換您的來電：

• $ xmlFile-> asXML（ 'data.xml中'）;
• $ sxe-> asXML（「data.xml」）;

有了：

• 中WriteXML（ 'data.xml中'，$ XMLFILE）;
• writeXML（'data.xml'，$ sxe）;

它應該可以工作。

//Writes final version of the SimpleXML object to file. 
//Includes writing to a temp file for safety. 
//This way is safer because if the code crashes mid-write it won't garble the original file. 
function writeXML($fileName, $xmlObject) 
{ 
     //Sanity check before copy, prevent any visible errors: 
     if (file_exists($fileName)) 
       copy($fileName, $fileName . '.backup'); 

     //Write to temp file first in-case something kills the write; don't want to corrupt the original. 
     $tmpName = $fileName . '~$.' . microtime(); 
     $handle = fopen($tmpName, 'w'); 
     fwrite($handle, formatXML($xmlObject)); 
     fclose($handle); 
     copy($tmpName, $fileName); 
     unlink($tmpName); 
} 

//asXML does no indentation formatting, so we'll do it here instead. This is called by WriteXML so that we're writing formatted XML to file. 
function formatXML($xmlObject) 
{ 
     $dom = new DOMDocument('1.0'); 
     $dom->preserveWhiteSpace = false; 
     $dom->formatOutput = true; 
     $dom->loadXML($xmlObject->asXML()); 
     return $dom->saveXML(); 
}