Delete pictures in php

In PHP, deleting images is a common task. Whether in website development or desktop applications, when operating pictures, you will encounter picture deletion.

The process of deleting a picture includes finding the picture file, deleting the picture file from the file system, and deleting the information related to the picture from the database (such as the picture file name, path, etc.). In this article, I will show you how to delete images in PHP.

1. Find the picture file

Before deleting the picture, we need to find the picture file first. This can be done using PHP's file handling functions. In PHP, you can use the following function to obtain image files:

// 获取目录下的所有文件
$files = scandir($dir);

foreach ($files as $file) {
  // 获取文件拓展名
  $ext = pathinfo($file, PATHINFO_EXTENSION);

  // 判断是否是图片文件
  if(in_array($ext, ['jpg', 'png', 'gif'])) {
    // 删除图片文件
    unlink("$dir/$file");
  }
}

The above code uses the scandir() function to obtain a list of all files in the directory where the image file is located. Then, we can iterate through the list and determine whether the extension of each file is of image type. We use the in_array() function to determine whether the file extension is in an array. In this example we use the ['jpg', 'png', 'gif'] array to determine .

If the extension of a file belongs to the image type, use the unlink() function to delete the file.

2. Delete the image file from the file system

After finding the file in the previous step, we need to delete the file from the file system. In PHP, you can use the unlink() function to delete files, for example:

unlink('/path/to/image.jpg');

When deleting files, please make sure you have sufficient permissions to perform the operation. If the file you want to delete was created by a web server, you may need to set the appropriate permissions on the web server.

3. Delete picture-related information from the database

After deleting the picture file, we need to delete the picture-related information from the database. This could be the image's filename, path, or other properties. Before deleting, we need to determine which database tables store this information and use the SQL delete command to delete the corresponding records. For example:

DELETE FROM images WHERE filename='image.jpg';

Before performing the deletion, please make sure you have backed up the data in the database. When a database record is deleted, the data is permanently lost.

4. Summary

Deleting images in PHP is a common task. To accomplish this task, we need to perform the following steps:

• Find the image file (using the scandir() function)
• Delete the image file from the file system ( Use the unlink() function)
• Delete image-related information from the database (use the SQL delete command)

Please note that deleting files and deleting databases Logging may have an impact on the runtime behavior of the application. Before performing a removal operation, carefully consider the impact and risks, and back up your applications and data.

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