使用PHP进行Bing自定义搜索

I'm in the process of testing the new Bing Custom Search using below PHP code. The result is a blank white screen with no errors. Is it because this service is still in beta mode?

<?php
$sURL = "https://api.cognitive.microsoft.com/bingcustomsearch/v5.0/search?q=dogs&customconfig=[mycustomconfigvalue]&responseFilter=Webpages&mkt=en-us&safesearch=Moderate";
$key = "[myPrimaryKey]";


$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $sURL); 
curl_setopt($ch, CURLOPT_TIMEOUT, '1'); 
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HEADER, 'ocp-apim-subscription-key:$key');
$content = curl_exec($ch);

echo $content;
?>

When I try to verify if API keys are working for me using Postman, I get an error saying "Could n ot get any response".

However, if I try the same values in https://customsearch.ai under endpoint section, it works perfectly by displaying the response.

Can anyone please let me know I can't run the code using my own PHP code?

Thanks

3 Errors:

1 - CURLOPT_HEADER is different from CURLOPT_HTTPHEADER.
2 - CURLOPT_HTTPHEADER takes an array as argument, not a string.
3 - Variables ($key) only expand inside double quotes.

Try:

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $sURL); 
curl_setopt($ch, CURLOPT_TIMEOUT, 1); # you may want increase this value
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["ocp-apim-subscription-key:$key"]);
$content = curl_exec($ch);

I replied this somewhere. Here is a working php snippet. Just replace YOUR_QUERY, YOUR_KEY, and YOUR_CUSTOMCONFIG.

$endpoint = 'https://api.cognitive.microsoft.com/bingcustomsearch/v7.0/search';
$term = 'YOUR_QUERY';
$headers = "Ocp-Apim-Subscription-Key: YOUR_KEY
";
$options = array ('http' => array (
                      'header' => $headers,
                       'method' => 'GET'));
$context = stream_context_create($options);
$result = file_get_contents($url . "?q=" . urlencode($query) . "&customconfig=YOUR_CUSTOMCONFIG&responseFilter=Webpages&mkt=en‌​-us&safesearch=Moder‌​ate", false, $context);