Mono for Android 拍照和本地图片选择上传到服务器

//添加图片
        public void btn_user_idcart_click(object sender, EventArgs e)
        {
            //Intent intent = new Intent(Intent.ActionPick, null);
            //intent.SetDataAndType(MediaStore.Images.Media.ExternalContentUri, "image/*");
			Intent intent = new Intent();
			intent.SetType("image/*");  
			intent.SetAction(Intent.ActionGetContent);  
			StartActivityForResult(intent, PHOTOZOOM);
        }

        //拍照
        public void btn_user_eidcart_click(object sender, EventArgs e)
        {
            var intent = new Intent(MediaStore.ActionImageCapture);
            var availableActivities = this.PackageManager.QueryIntentActivities(intent, PackageInfoFlags.MatchDefaultOnly);
            if (availableActivities != null && availableActivities.Count > 0)
            {
                var dir = new Java.IO.File(Android.OS.Environment.ExternalStorageDirectory.Path, "exuezhe");
                if (!dir.Exists())
                {
                    dir.Mkdirs();
                }
                _file = new Java.IO.File(dir, user.uname + ".jpg");
                intent.PutExtra(MediaStore.ExtraOutput, Android.Net.Uri.FromFile(_file));
                StartActivityForResult(intent, PHOTOHRAPH);

            }

        }
        //回调函数
        protected override void OnActivityResult(int requestCode, Result resultCode, Android.Content.Intent data)
        {
            base.OnActivityResult(requestCode, resultCode, data);

            if (requestCode == PHOTOZOOM)
            {
                if (data != null)
                {
                    StartPhotoZoom(data.Data);
                }
                //Android.Net.Uri uri = data.Data;
                //ContentResolver cr = this.ContentResolver;
                //Bitmap bitmap = BitmapFactory.DecodeStream(cr.OpenInputStream(uri));
                //MemoryStream stream = new MemoryStream();
                //bitmap.Compress(Bitmap.CompressFormat.Png, 50, stream);
                //byte[] buffer = stream.ToArray();
                //path = uapi.ModifyUserAva(buffer);
            }
            if (requestCode == PHOTOHRAPH)
            {
                if (_file != null)
                {
                    StartPhotoZoom(Android.Net.Uri.FromFile(_file));
                }

                //long len = _file.Length();
                //FileStream fs = new FileStream(_file.Path, FileMode.Open);
                //byte[] buffer = new byte[len];
                //fs.Read(buffer, 0, (int)len);
                //fs.Close();
                //path = uapi.ModifyUserAva(buffer);
            }
            if (requestCode == PHOTORESOULT)
            {
                if (data != null)
                {

                    SetPicToView(data);
                }

            }

        }
        //裁剪图片
        public void StartPhotoZoom(Android.Net.Uri uri)
        {
            Intent intent = new Intent("com.android.camera.action.CROP");
            intent.SetDataAndType(uri, "image/*");
            // 下面这个crop=true是设置在开启的Intent中设置显示的VIEW可裁剪
            intent.PutExtra("crop", "true");
            // aspectX aspectY 是宽高的比例
            intent.PutExtra("aspectX", 1);
            intent.PutExtra("aspectY", 1);
            // outputX outputY 是裁剪图片宽高
            intent.PutExtra("outputX", 150);
            intent.PutExtra("outputY", 150);
            intent.PutExtra("return-data", true);
            StartActivityForResult(intent, PHOTORESOULT);

        }
        //提交服务器
        private void SetPicToView(Intent picdata)
        {
            Bitmap bitmap=null;
            Bundle extras = picdata.Extras;
            if (extras != null)
            {
                 bitmap =(Bitmap)extras.GetParcelable("data");
            }
            ContentResolver cr = this.ContentResolver;
            //Bitmap bitmap = BitmapFactory.DecodeStream(cr.OpenInputStream(uri));
            MemoryStream stream = new MemoryStream();
            bitmap.Compress(Bitmap.CompressFormat.Png, 50, stream);
            byte[] buffer = stream.ToArray();
            //上次buffer
            //path = uapi.ModifyUserAva(buffer);

        }