How to Use pathinfo to Determine File Types and Execute Different PHP Logic

gitbox 2025-09-08

<?php<br>
// This part of the code is unrelated to the main content, just an example. Adjust as needed for actual use.<br>
echo "Program execution started.<br>";<br>
?></p>
<p><hr></p>
<p><?php<br>
/**</p>
<ul>
<li>
<p>How to use pathinfo to determine file types and execute different PHP logic</p>
</li>
<li></li>
<li>
<p>In PHP development, it's often necessary to perform different operations based on the file type, such as images, documents, or videos.</p>
</li>
<li>
<p>PHP's built-in pathinfo function makes it easy to get information about a file path, including the file extension, enabling type-based handling.</p>
</li>
<li></li>
<li>
<p>Here is a simple example showing how to use pathinfo to get the file extension and perform different actions based on the type.<br>
*/</p>
</li>
</ul>
<p>// Assume there is a file name<br>
$filename = "example.jpg";</p>
<p>// Get file information using pathinfo<br>
$fileInfo = pathinfo($filename);</p>
<p>// Get extension (convert to lowercase to avoid case sensitivity issues)<br>
$extension = strtolower($fileInfo['extension'] ?? "");</p>
<p>// Execute different logic based on extension<br>
switch ($extension) {<br>
case 'jpg':<br>
case 'jpeg':<br>
case 'png':<br>
case 'gif':<br>
echo "This is an image file, executing image processing logic.<br>";<br>
// Place image-related operations here, like thumbnail generation or compression<br>
break;</p>
</span><span><span class="hljs-keyword">case</span></span><span> </span><span><span class="hljs-string">'doc'</span></span><span>:
</span><span><span class="hljs-keyword">case</span></span><span> </span><span><span class="hljs-string">'docx'</span></span><span>:
    </span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"This is a document file, executing document processing logic.&lt;br&gt;"</span></span><span>;
    </span><span><span class="hljs-comment">// Place document-related operations here, like content parsing or format conversion</span></span><span>
    </span><span><span class="hljs-keyword">break</span></span><span>;

</span><span><span class="hljs-keyword">case</span></span><span> </span><span><span class="hljs-string">'mp4'</span></span><span>:
</span><span><span class="hljs-keyword">case</span></span><span> </span><span><span class="hljs-string">'avi'</span></span><span>:
</span><span><span class="hljs-keyword">case</span></span><span> </span><span><span class="hljs-string">'mov'</span></span><span>:
    </span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"This is a video file, executing video processing logic.&lt;br&gt;"</span></span><span>;
    </span><span><span class="hljs-comment">// Place video-related operations here, like transcoding or thumbnail extraction</span></span><span>
    </span><span><span class="hljs-keyword">break</span></span><span>;

</span><span><span class="hljs-keyword">default</span></span><span>:
    </span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"Unknown or unsupported file type, executing default logic.&lt;br&gt;"</span></span><span>;
    </span><span><span class="hljs-comment">// Place default logic here, like rejecting upload or showing an error</span></span><span>
    </span><span><span class="hljs-keyword">break</span></span><span>;

}

/**

Special notes:
1. pathinfo only parses the filename string itself; it does not verify if the file exists.
1. Extension-based checks rely on the file suffix, which may pose security risks (e.g., malicious renaming). Consider additional validation using mime_content_type if necessary.
1. Extensions should be standardized (usually with strtolower) to avoid case-sensitive misjudgments.
  */

pathinfo