php delete specified files

When developing with PHP, deleting specified files is a very common operation. This article will introduce how to delete specified files using PHP.

1. How to delete files using PHP

PHP deletes files by calling the unlink() function. The syntax of this function is as follows:

bool unlink ( string $filename [, resource $context ] )

The filename parameter is the file name to be deleted, and the context parameter is the optional file context.

If the deletion is successful, the function returns true; if the deletion fails, the function returns false.

2. Sample program

The following is a simple sample program that demonstrates how to use PHP to delete specified files:

<?php
$file = 'example.txt';

if (file_exists($file)) {
    if (unlink($file)) {
        echo "文件删除成功：$file";
    } else {
        echo "文件删除失败：$file";
    }
} else {
    echo "文件不存在：$file";
}
?>

3. Code analysis

1. First define the file name to be deleted $file.
2. Use the file_exists() function to detect whether the file exists. If the file exists, delete it, otherwise it will prompt that the file does not exist.
3. Use the unlink() function to delete the file. If the deletion is successful, file deletion success will be output: $file, otherwise file deletion failure will be output: $file .

4. Notes

1. # The unlink() function can only delete files, not directories.
2. When deleting a file, you need to pay attention to whether the file is in use. If the file is in use, it cannot be deleted.
3. In order to ensure the security of the system, permission verification should be performed when deleting files.

5. Summary

This article introduces how to use PHP to delete specified files. Specified files can be easily deleted by calling the unlink() function. When deleting files, you need to pay attention to whether the files are in use and perform permission verification to ensure system security.

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