


Determining File Existence on Remote Servers
Question: How can I ascertain the existence of a file on a remote server without utilizing file-related functions?
Answer: PHP's get_header function offers an efficient method to check file availability on remote servers without the need for complex mechanisms.
<code class="php">$headers=get_headers($url);</code>
By inspecting the response status code returned in $headers[0], you can determine if the file exists. A code of "200 OK" indicates that the file is present.
<code class="php">function UR_exists($url){ $headers=get_headers($url); return stripos($headers[0],"200 OK")?true:false; }</code>
This function returns a Boolean value indicating the existence or absence of the file at the specified URL. You can leverage it to test URL functionality, as exemplified below:
<code class="php">if(UR_exists("http://www.amazingjokes.com/")) echo "This page exists"; else echo "This page does not exist";</code>
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