How Can I Use PHP to Check if a Website is Available?

Pinging a Website and Retrieving Availability Status in PHP

Determining the availability of a website is a common task in web development. In this article, we will demonstrate how to ping a site and return a boolean representing its availability using PHP.

Solution

The following PHP function, urlExists, effectively pings a URL and returns true if the website is available and false if it is unavailable:

function urlExists($url=NULL)  
{  
    if($url == NULL) return false;  
    $ch = curl_init($url);  
    curl_setopt($ch, CURLOPT_TIMEOUT, 5);  
    curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 5);  
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);  
    $data = curl_exec($ch);  
    $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);  
    curl_close($ch);  

    return $httpcode >= 200 && $httpcode < 300;
}  

Explanation:

• The function takes a URL as input.
• It uses the PHP cURL library to initiate a connection to the URL.
• The CURLOPT_TIMEOUT and CURLOPT_CONNECTTIMEOUT options are set to 5 seconds for a quick response.
• After executing the cURL request, the function retrieves the HTTP response code ($httpcode).
• If the HTTP response code is in the range of 200 to 299, indicating a successful connection, the function returns true. Otherwise, it returns false.

The above is the detailed content of How Can I Use PHP to Check if a Website is Available?. For more information, please follow other related articles on the PHP Chinese website!