Xamarin.Forms——上传图片

效果图

1. 在所有平台增加Plugin.Media NutGet包
   
   
   1. 编写xaml
      <StackLayout>
<Button Text="上传图片" Clicked="Button_Clicked" />
</StackLayout>
      3.处理事件

 private async void Button_Clicked(object sender, EventArgs e)        {            string imgName= await TakeImageAction("123");        }

4.编写TakeImageAction()方法

    string action = await DisplayActionSheet("", "", "", "拍照", "从相册选择");            MediaFile pickFile = null;            switch (action)            {                case "拍照":                    //判断能否使用摄像头                    if (!CrossMedia.Current.IsCameraAvailable || !CrossMedia.Current.IsTakePhotoSupported)                    {                        await DisplayAlert("错误提示", "未找到可用摄像头", "确认");                    }                    var filea = await CrossMedia.Current.TakePhotoAsync(new Plugin.Media.Abstractions.StoreCameraMediaOptions                    {                        PhotoSize = Plugin.Media.Abstractions.PhotoSize.Medium,                        //拍照后的文件夹名                        Directory = "SjBIdrPics",                        //拍照后的文件名                        Name = "SjBIdr.jpg"                    });                    if (filea == null)                        return null;                    pickFile = filea;                    break;                case "从相册选择":                    //判断能否读取图片                    if (!CrossMedia.Current.IsPickPhotoSupported)                    {                        await DisplayAlert("错误提示", "未获得权限读取相册", "确认");                    }                    //选择图片                    var fileb = await Plugin.Media.CrossMedia.Current.PickPhotoAsync(new Plugin.Media.Abstractions.PickMediaOptions                    {                        PhotoSize = Plugin.Media.Abstractions.PhotoSize.Medium                    });                    if (fileb == null)                        return null;                    pickFile = fileb;                    break;            }                    if (pickFile != null)            {                //上传图片到服务器                HttpClient client = new HttpClient();                #region                MultipartFormDataContent form = new MultipartFormDataContent();                StreamContent fileContent = new StreamContent(pickFile.GetStream());                fileContent.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");                fileContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data");                fileContent.Headers.ContentDisposition.FileName = System.DateTime.Now.ToString("yyyMMddHHmmss") + "_" + UserName + ".jpg";                form.Add(fileContent);                #endregion                HttpResponseMessage res = await client.PostAsync("***/Test/ImageUpload", form);                var uploadModel = await res.Content.ReadAsStringAsync();                return uploadModel;                }            else            {                return "";            }

GitHub官方文档:https://github.com/jamesmontemagno/MediaPlugin