Android4.4 + WebAPI 实现拍照上传

     网上有很多关于拍照上传的实现方法，如果用新版本android去运行有可能会发现根本实现不了。主要原因是android从4.4版本开始通过intent.ACTION_GET_CONTENT打开选择器后，getData()返回的URI没有包含真实的文件路径，而是像这样“content://com.android.providers.media.documents/document/image:1234”，以至于用传统的方式找不到图片的路径。最简单的解决办法是用intent.ACTION_PICK代替intent.ACTION_GET_CONTENT。下面给出4.4版本后拍照上传的具体实现方法：

第一步：点击拍照按钮代码

        //点击拍照
        btnHeadCamera.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent itCamera=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                startActivityForResult(itCamera,0);
            }
        });

第二步：保存拍照图片代码

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode){
            case 0://拍照
                savePhoto(data);
                break;
        }
        super.onActivityResult(requestCode, resultCode, data);
    }

   final String SAVE_PATH=Environment.getExternalStorageDirectory()+"/my_head.jpg"; //拍照后保存路径 
    //保存图片
    public void savePhoto(Intent it){
        Bundle bundle=it.getExtras();
        if(bundle!=null){
            Bitmap photo = bundle.getParcelable("data");
            imgHead.setImageBitmap(photo);
            File fileHead=new File(SAVE_PATH);
            try {
                if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
                    if(!fileHead.getParentFile().exists()){
                        fileHead.getParentFile().mkdir();
                    }
                    BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream(fileHead));
                    photo.compress(Bitmap.CompressFormat.JPEG,80,bos);
                    bos.flush();
                    bos.close();
                }else {
                    Toast toast = Toast.makeText(HeadPhotoActivity.this, "保存失败！", Toast.LENGTH_SHORT);
                    toast.setGravity(Gravity.CENTER, 0, 0);
                    toast.show();
                }
            }catch (FileNotFoundException e){
                e.printStackTrace();
            }catch (IOException e){
                e.printStackTrace();
            }
        }
    }

第三步：上传图片代码

String SERVER_URL = Config.PhotoAPI+"/UploadImage";//上传的服务端API地址

btnHeadCancel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                new Thread(new Runnable() {
                    @Override
                    public void run() {
                        File file = new File(SAVE_PATH);
                        Message msg = new Message();
                        msg.what = 0;
                        if(file!=null) {
                            try {
                              int re = ImageUtils.uploadForm(file, SERVER_URL);
                                msg.obj = re;
                            } catch (IOException ex) {
                                msg.obj = 0;
                                Toast.makeText(HeadPhotoActivity.this, "上传失败", Toast.LENGTH_SHORT).show();
                            }
                            handler.sendMessage(msg);
                        }else {
                            Toast.makeText(HeadPhotoActivity.this, "找不到上传图片", Toast.LENGTH_SHORT).show();
                        }
                    }
                }).start();
            }
        });

final Handler handler=new Handler(){
            @Override
            public void handleMessage(Message msg) {
                switch (msg.what) {
                    case 0:
                        if ((int)msg.obj == 1) {
                            Toast.makeText(HeadPhotoActivity.this, "上传成功", Toast.LENGTH_SHORT).show();
                        } else {
                            Toast.makeText(HeadPhotoActivity.this, "上传失败", Toast.LENGTH_SHORT).show();
                        }
                        break;
                }

            }
        };

    /**
     *
     * @param uploadFile
     *            需要上传的文件
     * @param serverUrl
     *            上传的服务器的路径
     * @throws IOException
     */
    public static int uploadForm(File uploadFile,  String serverUrl)
            throws IOException {
        int re=0;

        String fileName = uploadFile.getName();
        StringBuilder sb = new StringBuilder();
　　　　　//带上参数,可添加多个参数
　　　　  sb.append("--" + BOUNDARY + "
");
        sb.append("Content-Disposition: form-data; name="paramName"" + "
");
        sb.append("
");
        sb.append("paramValue" + "
");

        sb.append("--" + BOUNDARY + "
");
        sb.append("Content-Disposition: form-data; name="" + fileName
                + ""; filename="" + fileName + """ + "
");
        sb.append("Content-Type: image/jpeg" + "
");
        sb.append("
");

        byte[] headerInfo = sb.toString().getBytes("UTF-8");
        byte[] endInfo = ("
--" + BOUNDARY + "--
").getBytes("UTF-8");
        System.out.println(sb.toString());
        URL url = new URL(serverUrl);
        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setRequestMethod("POST");
        conn.setRequestProperty("Content-Type",
                "multipart/form-data; boundary=" + BOUNDARY);
        conn.setRequestProperty("Content-Length", String
                .valueOf(headerInfo.length + uploadFile.length()
                        + endInfo.length));
        conn.setDoOutput(true);

        OutputStream out = conn.getOutputStream();
        InputStream in = new FileInputStream(uploadFile);
        out.write(headerInfo);

        byte[] buf = new byte[1024];
        int len;
        while ((len = in.read(buf)) != -1)
            out.write(buf, 0, len);

        out.write(endInfo);
        in.close();
        out.close();
        if (conn.getResponseCode() == 200) {
            re=1;
        }
        return re;
    }

最后给出服务端WebAPI代码：

        [HttpPost]
        public async Task<HttpResponseMessage> UploadImage()
        {
string filePath = "~\UploadFiles\Photo";
            // 取得文件夹
            string dir = HttpContext.Current.Server.MapPath(filePath);
            //如果不存在文件夹，就创建文件夹
            if (!Directory.Exists(dir))
                Directory.CreateDirectory(dir);
            if (!Request.Content.IsMimeMultipartContent("form-data"))
            {
                throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
            }
            var provider = new CustomMultipartFormDataStreamProvider(dir);
            try
            {
                // Read the form data. 
                await Request.Content.ReadAsMultipartAsync(provider);
                foreach (MultipartFileData file in provider.FileData)
                {
                    //file.Headers.ContentDisposition.FileName;//上传文件前的文件名
                    //file.LocalFileName;//上传后的文件名
                    Photo p = new Photo();
                    p.ImgInfo = file.LocalFileName.Substring(file.LocalFileName.LastIndexOf("\"));
                    p.Sort = "员工相册";
                    p.AddUser = "admin";
                    p.AddTime = DateTime.Now;
                    p.Url = filePath + p.ImgInfo;

                    db.Photo.Add(p);
                    db.SaveChanges();
                }
                return Request.CreateResponse(HttpStatusCode.OK);
            }
            catch
            {
                return Request.CreateResponse(HttpStatusCode.BadRequest);
            }
        }

    //重写上传文件名
    public class CustomMultipartFormDataStreamProvider : MultipartFormDataStreamProvider 
    {
        public CustomMultipartFormDataStreamProvider(string path)
            : base(path)
        { }

        public override string GetLocalFileName(System.Net.Http.Headers.HttpContentHeaders headers)
        {
            string fileName = DateTime.Now.ToString("yyyyMMddHHmmssfff");
            return fileName + "_" + headers.ContentDisposition.FileName.Replace(""", string.Empty);//base.GetLocalFileName(headers);
        }
    }