? File Upload in PHP

PHP makes it easy to upload files like images, documents, and more using a simple HTML form and the $_FILES superglobal.

? Step 1: Create the HTML Upload Form

<!-- upload.html --><form action="upload.php" method="post" enctype="multipart/form-data">  Select file to upload:  <input type="file" name="myfile">  <input type="submit" value="Upload File"></form>

? The enctype="multipart/form-data" is required for file uploads!

? Step 2: Handle the Upload in PHP

<?php// upload.phpif ($_SERVER['REQUEST_METHOD'] == 'POST') {    $target_dir = "uploads/"; // Make sure this folder exists and is writable    $target_file = $target_dir . basename($_FILES["myfile"]["name"]);    if (move_uploaded_file($_FILES["myfile"]["tmp_name"], $target_file)) {        echo "The file " . htmlspecialchars(basename($_FILES["myfile"]["name"])) . " has been uploaded.";    } else {        echo "Sorry, there was an error uploading your file.";    }}?>

? $_FILES Array Breakdown

$_FILES['myfile']['name']      // Original filename$_FILES['myfile']['type']      // MIME type (e.g., image/jpeg)$_FILES['myfile']['size']      // File size in bytes$_FILES['myfile']['tmp_name']  // Temp file path$_FILES['myfile']['error']     // Error code (0 = OK)

? Best Practices

• ? Check file size

• ? Validate file type (e.g., only allow images or PDFs)

• ? Sanitize file names

• ? Set permissions on upload folder

• ? Avoid directly using user input for file paths

? Example: Allow Only Images

$allowedTypes = ['jpg', 'jpeg', 'png', 'gif'];$fileType = strtolower(pathinfo($target_file, PATHINFO_EXTENSION));if (!in_array($fileType, $allowedTypes)) {    echo "Only JPG, JPEG, PNG & GIF files are allowed.";    exit;}

? Sample Folder Structure

project/??? upload.html??? upload.php??? uploads/         ? must be writable (e.g. chmod 755 or 777)