Unity3D(C#)向PHP服务器指定文件夹上传文本文件的实现需求

Alright, let's put together this targeted file upload system for your Unity project and PHP server. You already have a basic module that turns strings into text files, so we'll extend that to support uploading to a specified folder—with the server automatically creating the folder if it doesn't exist. Here's how to do it:

First, we'll modify your existing string-to-text-file module to include uploading to a specified folder. We'll use UnityWebRequest to send a multipart form request, which lets us send both the folder name and the text file data in one go.

Here's the updated client code:

using UnityEngine;
using UnityEngine.Networking;
using System.IO;

public class FileUploader : MonoBehaviour
{
    // Replace this with your actual server PHP endpoint URL
    [SerializeField] private string uploadUrl = "http://your-server-domain.com/upload.php";

    // Call this method to upload your text content to a target folder
    public void UploadTextToFolder(string textContent, string targetFolder, string fileName)
    {
        // Create a temporary text file from your string (you might already have this logic)
        string tempFilePath = Path.Combine(Application.temporaryCachePath, fileName);
        File.WriteAllText(tempFilePath, textContent);

        // Start the async upload coroutine
        StartCoroutine(UploadFileCoroutine(tempFilePath, targetFolder, fileName));
    }

    private IEnumerator UploadFileCoroutine(string filePath, string targetFolder, string fileName)
    {
        // Package the folder name and file into a form
        WWWForm formData = new WWWForm();
        formData.AddField("target_folder", targetFolder);
        formData.AddBinaryData("uploaded_file", File.ReadAllBytes(filePath), fileName, "text/plain");

        using (UnityWebRequest webRequest = UnityWebRequest.Post(uploadUrl, formData))
        {
            yield return webRequest.SendWebRequest();

            // Handle server response
            if (webRequest.result != UnityWebRequest.Result.Success)
            {
                Debug.LogError($"Upload failed: {webRequest.error}");
            }
            else
            {
                Debug.Log($"Upload successful! Server says: {webRequest.downloadHandler.text}");
                // Clean up the temporary file to avoid clutter
                File.Delete(filePath);
            }
        }
    }
}

Quick Notes for Unity Side: #

• We use WWWForm to bundle both the target folder name and file data—this makes it easy for the PHP server to access both values.
• The temporary file is stored in Unity's cache directory and deleted right after upload.
• Don't forget to replace uploadUrl with your actual server endpoint.

On the server side, we need to handle three core tasks: retrieve the target folder, create it if it doesn't exist, and safely store the uploaded file. We'll also add security checks to avoid common vulnerabilities.

Here's the complete upload.php code:

<?php
// Enable error reporting for debugging (turn this off in production!)
error_reporting(E_ALL);
ini_set('display_errors', 1);

// Define the base directory where all upload folders will live
// Make sure this folder has write permissions for your web server
$baseUploadDir = './uploads/';

// Check if we received the required data from the client
if (!isset($_POST['target_folder']) || !isset($_FILES['uploaded_file'])) {
    echo json_encode(['status' => 'error', 'message' => 'Missing required parameters']);
    exit;
}

$targetFolder = $_POST['target_folder'];
$uploadedFile = $_FILES['uploaded_file'];

// Sanitize the folder name to block path traversal attacks (e.g., ../../malicious-folder)
$safeFolderName = preg_replace('/[^a-zA-Z0-9_\-]/', '', $targetFolder);
$fullTargetDir = $baseUploadDir . $safeFolderName . '/';

// Step 1: Create the target folder if it doesn't exist
if (!is_dir($fullTargetDir)) {
    // Create folder with 0755 permissions (read/write for owner, read-only for others)
    if (!mkdir($fullTargetDir, 0755, true)) {
        echo json_encode(['status' => 'error', 'message' => 'Failed to create target folder']);
        exit;
    }
}

// Step 2: Validate the uploaded file
if ($uploadedFile['error'] !== UPLOAD_ERR_OK) {
    $errorMap = [
        UPLOAD_ERR_INI_SIZE => 'File is too big (exceeds server upload limit)',
        UPLOAD_ERR_FORM_SIZE => 'File is too big (exceeds client-side limit)',
        UPLOAD_ERR_PARTIAL => 'File was only partially uploaded',
        UPLOAD_ERR_NO_FILE => 'No file was sent',
        UPLOAD_ERR_NO_TMP_DIR => 'Server is missing a temporary storage folder',
        UPLOAD_ERR_CANT_WRITE => 'Server can\'t write the file to disk',
        UPLOAD_ERR_EXTENSION => 'File upload was stopped by a server extension'
    ];
    $errorMsg = $errorMap[$uploadedFile['error']] ?? 'Unknown upload error';
    echo json_encode(['status' => 'error', 'message' => $errorMsg]);
    exit;
}

// Step 3: Move the uploaded file to its target folder
$targetFilePath = $fullTargetDir . basename($uploadedFile['name']);
if (move_uploaded_file($uploadedFile['tmp_name'], $targetFilePath)) {
    echo json_encode(['status' => 'success', 'message' => 'File uploaded successfully', 'file_path' => $targetFilePath]);
} else {
    echo json_encode(['status' => 'error', 'message' => 'Failed to move the uploaded file']);
}
?>

Quick Notes for PHP Side: #

• Security: We sanitize the folder name to prevent attackers from uploading files to unintended directories.
• Permissions: The mkdir call uses true for recursive creation, so parent folders will be created if needed. Ensure your web server has write access to the uploads/ directory (run chmod 755 uploads/ or chown www-data:www-data uploads/ depending on your server setup).
• Error Handling: We return JSON responses so the Unity client can easily parse success/error states.

Final Setup Steps: #

1. Create the base uploads/ directory on your server and set proper write permissions.
2. Test the system by calling UploadTextToFolder("Hello World!", "Folder1", "test.txt") from your Unity code. You should see Folder1 created inside uploads/ with test.txt inside it.

内容的提问来源于stack exchange，提问作者Filip