What are some common methods for generating unique filenames for uploaded files in PHP?

When uploading files in PHP, it is important to generate unique filenames to prevent overwriting existing files and ensure file integrity. Common methods for generating unique filenames include using a combination of timestamp and random characters, hashing the file contents, or appending a unique identifier to the original filename. 

// Generate a unique filename using timestamp and random characters
$uniqueFilename = time() . '_' . uniqid() . '_' . $_FILES['file']['name'];
```

```php
// Generate a unique filename by hashing the file contents
$uniqueFilename = md5_file($_FILES['file']['tmp_name']) . '_' . $_FILES['file']['name'];
```

```php
// Generate a unique filename by appending a unique identifier to the original filename
$uniqueFilename = uniqid() . '_' . $_FILES['file']['name'];

Keywords

UUID uniqid hash timestamp randomization

Related Questions