Accessing file meta data and getting the file creation date is an important aspect of managing and organizing digital contents. This can be quite handy for developers who build applications that work with files, such as content management system, file management softwares and so on. We often need to display details like when a file was created, the file size, or its last modification date. In PHP, a number of built-in functions are available that can help you fetch these kind of file details. In this case, we’ll be using the filemtime() function to get the file’s creation date.
In PHP, the filemtime() function is used to return the last modification time of a specified file. This function returns the time in a Unix timestamp format, which represents the number of seconds elapsed since January 1 1970 00:00:00 GMT.
<?php
$file = 'example.txt';
//Gets the file creation time
$fileCreationTime = filemtime($file);
//Formats the time in a readable format
$fileCreationTime = date("F d, Y H:i:s.", $fileCreationTime);
echo "The file was last modified: " . $fileCreationTime;
?>
In the code above, we first specify the file we want to get the creation time for. Then, we use the filemtime() function, passing in the filename as a parameter. The function returns a Unix timestamp, which we then convert into a readable date and time with the date() function. Finally, we echo out the time in a readable format.
Exploring PHP Built-in Functions
Under PHP, there are multiple functions that address operations related to file handling. In built functions like file_exists() checks whether a file or directory exists, filesize() fetches the file size, and filetype() determines file type. However, in this context filectime() and filemtime() are particularly used for getting file creation and modification time.
Understanding Unix Timestamps
A Unix Timestamp is commonly used in PHP and stands for the number of seconds elapsed since January 1 1970 00:00:00 GMT. Functions such as filemtime() and filectime() return these timestamps. We can then convert this timestamp into a more human-readable format using the PHP date() function.
PHP not only gives us the power to create dynamic web pages, but also handle files and directories. This includes the ability to fetch metadata about files, like when they were created or last accessed, their size, type and even more. This part of PHP is something every PHP developer should understand and makes this language very well-rounded – from front-end web development right through to back-end file management.
Note: The creation time returned by filectime() or filemtime() is dependent on the information provided by the file system and may not always hold the correct values, particularly on certain operating systems or in certain scenarios. It is important to be aware of these potential limitations when working with file meta data in PHP.
