In what ways can PHP code be optimized to efficiently handle file uploads and image retrieval processes in a web development project?

To optimize PHP code for file uploads and image retrieval processes, it is important to use proper validation and error handling to ensure security and reliability. Additionally, using functions like move_uploaded_file() for file uploads and imagecreatefromjpeg() for image retrieval can help streamline the processes and improve performance.

// File upload optimization
if(isset($_FILES['file'])){
    $target_dir = "uploads/";
    $target_file = $target_dir . basename($_FILES["file"]["name"]);
    
    if (move_uploaded_file($_FILES["file"]["tmp_name"], $target_file)) {
        echo "File uploaded successfully.";
    } else {
        echo "Error uploading file.";
    }
}

// Image retrieval optimization
$image_path = "images/example.jpg";
$image = imagecreatefromjpeg($image_path);

// Display the image
header('Content-Type: image/jpeg');
imagejpeg($image);
imagedestroy($image);