如何通过蓝牙从安卓手机向电脑传输多张图片？

Alright, let's fix up your 32feet.net OBEX code to handle multiple image transfers from Android to your PC. Here's what you need to know and the revised implementation:

Key Background on OBEX Multi-File Transfers #

When you send multiple images from an Android device over Bluetooth, it typically sends them as multiple PUT requests within the same OBEX connection session. Your original code only handles a single request per connection context, which is why it misses subsequent images. We need to adjust the logic to process all requests from a single connection before moving to the next one.

Revised Code with Multi-Image Support #

using System;
using System.IO;
using System.Linq;
using InTheHand.Net.Obex;

// Initialize and start the Bluetooth OBEX listener
ObexListener mBtListener = new ObexListener(ObexTransport.Bluetooth);
mBtListener.Start();

string mUploadFolder = @"C:\BluetoothImageUploads"; // Update this to your target folder
Directory.CreateDirectory(mUploadFolder); // Ensure the folder exists to avoid IO errors

Console.WriteLine("OBEX Bluetooth listener started. Waiting for Android connections...");

try
{
    while (mBtListener.IsListening)
    {
        // Get the connection context (one per Android device connection)
        ObexListenerContext obexContext = mBtListener.GetContext();
        if (obexContext == null) continue;

        Console.WriteLine($"New connection from device: {obexContext.RemoteEndPoint}");

        try
        {
            // Process ALL requests from this connection (handles multiple images in one session)
            while (true)
            {
                ObexListenerRequest req = obexContext.GetRequest();
                if (req == null) break; // No more requests in this session

                try
                {
                    // Extract the original filename from OBEX headers
                    if (!req.Headers.Contains(ObexHeaderName.Name))
                    {
                        Console.WriteLine("Skipping request: No filename provided");
                        req.StatusCode = ObexStatusCode.BadRequest;
                        req.Close();
                        continue;
                    }

                    string originalFileName = req.Headers[ObexHeaderName.Name].ToString();
                    string savePath = Path.Combine(mUploadFolder, originalFileName);

                    // Avoid overwriting existing files by adding a counter suffix
                    int fileCounter = 1;
                    while (File.Exists(savePath))
                    {
                        string baseName = Path.GetFileNameWithoutExtension(originalFileName);
                        string extension = Path.GetExtension(originalFileName);
                        savePath = Path.Combine(mUploadFolder, $"{baseName}_{fileCounter}{extension}");
                        fileCounter++;
                    }

                    // Only save valid image files
                    if (IsImage(originalFileName))
                    {
                        req.WriteFile(savePath);
                        Console.WriteLine($"✅ Saved image: {savePath}");
                        req.StatusCode = ObexStatusCode.Success;
                    }
                    else
                    {
                        Console.WriteLine($"❌ Skipping non-image file: {originalFileName}");
                        req.StatusCode = ObexStatusCode.NotAcceptable;
                    }

                    req.Close();
                }
                catch (Exception ex)
                {
                    Console.WriteLine($"⚠️ Error processing request: {ex.Message}");
                    req?.Close();
                }
            }
        }
        finally
        {
            obexContext.Close();
            Console.WriteLine("🔌 Connection closed");
        }
    }
}
catch (Exception ex)
{
    Console.WriteLine($"❌ Listener failure: {ex.Message}");
}
finally
{
    mBtListener.Stop();
    Console.WriteLine("Listener stopped");
}

// Helper method to validate image file extensions
private bool IsImage(string fileName)
{
    string[] validImageExtensions = { ".jpg", ".jpeg", ".png", ".gif", ".bmp", ".webp" };
    string fileExtension = Path.GetExtension(fileName).ToLowerInvariant();
    return validImageExtensions.Contains(fileExtension);
}

Critical Changes Explained #

• Nested Request Loop: After getting a connection context, we add an inner while(true) loop to call GetRequest() repeatedly. This captures all images sent in the same OBEX session from Android.
• Filename Deduplication: Added logic to avoid overwriting existing files by appending a counter to duplicate filenames.
• Robust Error Handling: Wrapped request processing in try/catch blocks so a single failed transfer doesn't take down the entire listener.
• Explicit Status Codes: Return clear OBEX status codes to the Android device (success, bad request, not acceptable) so it knows how the transfer went.
• Folder Initialization: Ensured the upload folder exists before saving files to avoid unexpected IO errors.

Additional Notes #

• Make sure your PC's Bluetooth is discoverable and paired with the Android device.
• Android's default share menu uses OBEX for Bluetooth file transfers, so selecting multiple images and sharing via Bluetooth should work seamlessly with this code.
• Keep your 32feet.net NuGet package updated to the latest stable version to avoid known OBEX session bugs.

内容的提问来源于stack exchange，提问作者Явор Налбантов