使用 json_encode 格式看起来很糟糕[重复]

Question

我正在尝试使用 SimpleXML 从 MRSS 提要中解析出一些数据，然后使用该数据创建 JSON。

这是我正在尝试的，它确实输出 JSON，但格式看起来很糟糕，并且在每个元素之前给出所有 [{"0":"，我确定我做错了什么：

<?php
session_start();
$html = "";
$url = "http://feeds.nascar.com/feeds/video?command=search_videos&media_delivery=http&custom_fields=adtitle%2cfranchise&page_size=100&sort_by=PUBLISH_DATE:DESC&token=217e0d96-bd4a-4451-88ec-404debfaf425&any=franchise:%20Preview%20Show&any=franchise:%20Weekend%20Top%205&any=franchise:Up%20to%20Speed&any=franchise:Press%20Pass&any=franchise:Sprint%20Cup%20Practice%20Clips&any=franchise:Sprint%20Cup%20Highlights&any=franchise:Sprint%20Cup%20Final%20Laps&any=franchise:Sprint%20Cup%20Victory%20Lane&any=franchise:Sprint%20Cup%20Post%20Race%20Reactions&any=franchise:All%20Access&any=franchise:Nationwide%20Series%20Qualifying%20Clips&any=franchise:Nationwide%20Series%20Highlights&any=franchise:Nationwide%20Series%20Final%20Laps&any=franchise:Nationwide%20Series%20Victory%20Lane&any=franchise:Nationwide%20Series%20Post%20Race%20Reactions&any=franchise:Truck%20Series%20Qualifying%20Clips&any=franchise:Truck%20Series%20Highlights&any=franchise:Truck%20Series%20Final%20Laps&any=franchise:Truck%20Series%20Victory%20Lane&any=franchise:Truck%20Series%20Post%20Race%20Reactions&output=mrss";
$xml = simplexml_load_file($url);
$namespaces = $xml->getNamespaces(true); // get namespaces

for($i = 0; $i < 50; $i++){ // will return the 50 most recent videos 
  $title = $xml->channel->item[$i]->video;
  $link = $xml->channel->item[$i]->link;
  $title = $xml->channel->item[$i]->title;
  $pubDate = $xml->channel->item[$i]->pubDate;
  $description = $xml->channel->item[$i]->description;
  $titleid = $xml->channel->item[$i]->children($namespaces['bc'])->titleid;
  $m_attrs = $xml->channel->item[$i]->children($namespaces['media'])->content[0]->attributes();
$VideoFileURL = $m_attrs["url"];

$arr = array($title, $description, $VideoFileURL);

$json_string = json_encode($arr, 128);

echo json_encode($arr, 128);
}

?>

我都试过了

$json_string = json_encode($arr, 128)

和

$json_string = json_encode($arr, JSON_PRETTY_PRINT)

“128”的打印效果似乎比“JSON_PRETTY_PRINT”好

有什么想法吗？我确信这很明显，但我是 PHP 的新手。谢谢！

Answer 1

您需要将元素转换为字符串。如果您不将它们转换为字符串，它们就是 SimpleXMLElements。如果你这样做var_dump($title);，你会得到object(SimpleXMLElement)[6] public 0 => string 'Weekend Top 5: Talladega' (length=24)，这就是为什么你在每个元素之前都得到[{"0":"。

<?php
session_start();
$html = "";
$url = "http://feeds.nascar.com/feeds/video?command=search_videos&media_delivery=http&custom_fields=adtitle%2cfranchise&page_size=100&sort_by=PUBLISH_DATE:DESC&token=217e0d96-bd4a-4451-88ec-404debfaf425&any=franchise:%20Preview%20Show&any=franchise:%20Weekend%20Top%205&any=franchise:Up%20to%20Speed&any=franchise:Press%20Pass&any=franchise:Sprint%20Cup%20Practice%20Clips&any=franchise:Sprint%20Cup%20Highlights&any=franchise:Sprint%20Cup%20Final%20Laps&any=franchise:Sprint%20Cup%20Victory%20Lane&any=franchise:Sprint%20Cup%20Post%20Race%20Reactions&any=franchise:All%20Access&any=franchise:Nationwide%20Series%20Qualifying%20Clips&any=franchise:Nationwide%20Series%20Highlights&any=franchise:Nationwide%20Series%20Final%20Laps&any=franchise:Nationwide%20Series%20Victory%20Lane&any=franchise:Nationwide%20Series%20Post%20Race%20Reactions&any=franchise:Truck%20Series%20Qualifying%20Clips&any=franchise:Truck%20Series%20Highlights&any=franchise:Truck%20Series%20Final%20Laps&any=franchise:Truck%20Series%20Victory%20Lane&any=franchise:Truck%20Series%20Post%20Race%20Reactions&output=mrss";
$xml = simplexml_load_file($url);
$namespaces = $xml->getNamespaces(true); // get namespaces

for($i = 0; $i < 50; $i++){ // will return the 50 most recent videos 
  $title = (string)$xml->channel->item[$i]->video;
  $link = (string)$xml->channel->item[$i]->link;
  $title = (string)$xml->channel->item[$i]->title;
  $pubDate = (string)$xml->channel->item[$i]->pubDate;
  $description = (string)$xml->channel->item[$i]->description;
  $titleid = (string)$xml->channel->item[$i]->children($namespaces['bc'])->titleid;
  $m_attrs = $xml->channel->item[$i]->children($namespaces['media'])->content[0]->attributes();
  $VideoFileURL = (string)$m_attrs["url"];

  $arr = array('title' => $title, 'description' => $description, 'VideoFileURL' => $VideoFileURL);
  $json_string = json_encode($arr, JSON_PRETTY_PRINT);

  echo json_encode($arr, JSON_PRETTY_PRINT);
}

?>