Reputation: 185
I am trying to upload an image from my windows phone 8 app to the SQL server database using a WebAPI. I am using a model class for the Images, which simply consists of an ID belonging to the item the image is for, the name of the image and a byte array to hold the image itself. I use a WebClient object to access the WebAPI method. When I try to upload the image, it throws the exception as shown below. Does anyone have an idea why it errors? Also, I am open to other methods of storing the image to my SQL database. Thanks for having a look!
Code
private MemoryStream photoStream;
...
private void upload()
{
try
{
Images image = new Images();
image.ImagesBytes = photoStream.ToArray();
image.ImagesID = 3;
image.ImagesCaption = "this is a test";
string jsonData = JsonConvert.SerializeObject(image);
WebClient webClient = new WebClient();
webClient.Headers["Content-type"] = "application/json";
webClient.Encoding = Encoding.UTF8;
Uri uri = new Uri("http://myIP/api/Images/", UriKind.Absolute);
webClient.UploadStringCompleted += new UploadStringCompletedEventHandler(webClient_UploadStringCompleted);
webClient.UploadStringAsync(uri, "GET", jsonData);
}
catch
{
// Display the Uploaded message
tbError.Visibility = Visibility.Visible;
}
}
....
void webClient_UploadStringCompleted(object sender, UploadStringCompletedEventArgs e)
{
try
{
Images image = JsonConvert.DeserializeObject<Images>(e.Result);
}
catch (Exception ex)
{
// Display the Uploaded message
tbError.Visibility = Visibility.Visible;
}
}
Exception
System.Net.ProtocolViolationException: Operation is not valid due to the current state of the object.
at System.Net.Browser.ClientHttpWebRequest.InternalBeginGetRequestStream(AsyncCallback callback, Object state)
at System.Net.Browser.ClientHttpWebRequest.BeginGetRequestStream(AsyncCallback callback, Object state)
at System.Net.WebClient.UploadBits(WebRequest request, Stream readStream, Byte[] buffer, Byte[] header, Byte[] footer, CompletionDelegate completionDelegate, AsyncOperation asyncOp)
at System.Net.WebClient.UploadDownloadBits(WebRequest request, Stream readStream, Stream writeStream, Byte[] buffer, Byte[] header, Byte[] footer, CompletionDelegate upCompletionDelegate, CompletionDelegate downCompletionDelegate, AsyncOperation asyncOp)
at System.Net.WebClient.UploadStringAsync(Uri address, String method, String data, Object userToken)
Upvotes: 2
Views: 2657
Reputation: 11246
I believe your HTTP method is incorrect.
Instead of ...
webClient.UploadStringAsync(uri, "GET", jsonData);
try ...
webClient.UploadStringAsync(uri, "POST", jsonData);
Upvotes: 1