/// <summary>
/// This method creates a BackgroundTransferRequest object based on the information
/// of the ITransferable object passed as a parameter. The BackgroundTransferRequest
/// is then addedd to the BackgroundTransferService queue.
/// </summary>
/// <param name="Item">The ITransferable item.</param>
/// <returns>True, if the BackgroundTransferRequest has been created and added successfully to the BackgroundTransferService.</returns>
private bool AddTransferRequest(ITransferable Item)
{
//TODO: Improve validation of Item.TransferUri and Item.TransferLocationUri -> If URI is not valid then the object will not be removable
// First, validate the TransferURI
Uri TransferUri;
if (!Uri.TryCreate(Item.TransferUrl, UriKind.Absolute, out TransferUri) || String.IsNullOrEmpty(Item.TransferUrl) || String.IsNullOrWhiteSpace(Item.TransferUrl))
{
#if DEBUG
// In debug mode show MessageBox with exception details.
MessageBox.Show("I'm unable to add the background transfer request due to a malformed remote URI (" + Item.TransferUrl + ").", "Unable to start transfer", MessageBoxButton.OK);
#endif
return false;
}
// Second, validate the TransferLocation
Uri TransferLocation;
if (!Uri.TryCreate(Item.FilenameWithPath, UriKind.Relative, out TransferLocation) || String.IsNullOrEmpty(Item.FilenameWithPath) || String.IsNullOrWhiteSpace(Item.FilenameWithPath))
{
#if DEBUG
// In debug mode show MessageBox with exception details.
MessageBox.Show("I'm unable to add the background transfer request due to a malformed local URI (" + Item.TransferLocationUri + ").", "Unable to start transfer", MessageBoxButton.OK);
#endif
return false;
}
// A new BackgroundTransferRequest is created by passing the TransferUri of the ITransferable object.
BackgroundTransferRequest TransferRequest = new BackgroundTransferRequest(Item.TransferUri);
// Set the transfer properties according to the TransferSettings of the ITransferable object
#region Set transfer properties
try
{
TransferRequest.Method = Item.Method; // GET or POST
if (TransferRequest.Method == "GET")
{ // The temporary transfer location for download
TransferRequest.DownloadLocation = Item.TransferLocationUri;
}
else
{// The temporary transfer location for upload
TransferRequest.UploadLocation = Item.TransferLocationUri;
}
}
catch (ArgumentException)
{
#if DEBUG
// In debug mode show MessageBox with exception details.
MessageBox.Show("I'm unable to add the background transfer request due to a malformed local URI (" + Item.TransferLocationUri + ").", "Unable to start transfer", MessageBoxButton.OK);
#endif
return false;
}
TransferRequest.Tag = Item.UID.ToString(); // The TransferId
//TransferRequest.Headers.Add(Item.Headers); // Additional headers
TransferRequest.TransferPreferences = TransferSettings.I.TransferPreferences; // Transfer preferences such as None, AllowCellular, AllowBattery, AllowCellularAndBattery.
#endregion
// We register the event handlers for the progress change
TransferRequest.TransferProgressChanged += Item.TransferProgressChanged;
// The BackgroundTransferRequest is ready to be addedd to the BackgroundTransferService queue.
// Before adding, we call the ITransferable BeforeAdding() method to perform additional
// operations (e.g. placing the file in the right folder).
Item.OnBeforeAdd();
// Now the BackgroundTrabsferRequest is ready to be added to the BackgroundTransferService queue
// A try/catch block is necessary to handle the possible exceptions
TransferRequest.TransferStatusChanged += new EventHandler<BackgroundTransferEventArgs>(TransferRequest_TransferStatusChanged); // Transfer manager handler for status change
try
{
BackgroundTransferService.Add(TransferRequest);
// If add was successful we can retrieve the RequestId value and store it in the ITransferable object
// The RequestId is generated right after the instantiation of the BackgroundTransferRequest, but to
// avoid overwriting a previous value on the ITransferable object, we store it only after "Add" is
// successful (which means that the same object is not currently transferring).
Item.RequestId = TransferRequest.RequestId;
lock (this)
{
// We increment the internal counter
_ActiveBackgroundTransfers++;
}
var BackgroundTransfers = BackgroundTransferService.Requests;
// The BackgroundTransferRequest was successfully added to the BackgroundTransferService queue.
return true;
}
catch (BackgroundTransferInternalException ex)
{ //BackgroundTransferInternalException is thrown when:
// - The total request limit across all applications has been reached.
// - The HTTP network provider returned an error.
// - The HTTP network provider returned an error related to content-range request or response.
// - The HTTP network provider returned a network-related error.
// - The HTTP network provider returned a slow transfer error.
// - The isolated storage provider returned an error.
#if DEBUG
// In debug mode show MessageBox with exception details.
MessageBox.Show("I'm unable to add the background transfer request (BackgroundTransferInternalException). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
#endif
}
catch (InvalidOperationException ex)
{ // InvalidOperationException is thrown when:
// - The request has already been submitted.
// - The maximum number of requests per application has been reached.
// - A request with the same DownloadLocation URI has already been submitted.
// - The user has disabled background tasks in the device’s Settings.
#if DEBUG
// In debug mode show MessageBox with exception details.
MessageBox.Show("I'm unable to add the background transfer request (InvalidOperationException). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
#endif
}
catch (SystemException ex)
{ //SystemException is thrown when:
// - The maximum number of requests on the device has been reached.
// - The underlying transport layer returned an error.
// - The underlying transport layer returned an error related to the content-range request or response.
// - There is not enough space on the disk.
if (ex.Message == "There is not enough space on the disk.")
{
MessageBox.Show("There is not enough space on the device to start the transfer. Please free up some space and then retry.", "Unable to start transfer", MessageBoxButton.OK);
}
#if DEBUG
// In debug mode show MessageBox with exception details.
MessageBox.Show("I'm unable to add the background transfer request (SystemException). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
#endif
}
catch (Exception ex)
{
#if DEBUG
// In debug mode show MessageBox with exception details.
MessageBox.Show("I'm unable to add the background transfer request (Exception). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
#endif
}
return false;
}
/// <summary>
/// This method creates a BackgroundTransferRequest object based on the information
/// of the ITransferable object passed as a parameter. The BackgroundTransferRequest
/// is then addedd to the BackgroundTransferService queue.
/// </summary>
/// <param name="Item">The ITransferable item.</param>
/// <returns>True, if the BackgroundTransferRequest has been created and added successfully to the BackgroundTransferService.</returns>
private bool AddTransferRequest(ITransferable Item)
{
// A new BackgroundTransferRequest is created by passing the TransferUri of the ITransferable object.
BackgroundTransferRequest TransferRequest = new BackgroundTransferRequest(Item.TransferUri);
// Set the transfer properties according to the TransferSettings of the ITransferable object
#region Set transfer properties
TransferRequest.Method = Item.Method; // GET or POST
if (TransferRequest.Method == "GET")
{ // The temporary transfer location for download
TransferRequest.DownloadLocation = Item.TransferLocationUri;
}
else
{// The temporary transfer location for upload
TransferRequest.UploadLocation = Item.TransferLocationUri;
}
TransferRequest.Tag = Item.UID.ToString(); // The TransferId
//TransferRequest.Headers.Add(Item.Headers); // Additional headers
TransferRequest.TransferPreferences = TransferSettings.I.TransferPreferences; // Transfer preferences such as None, AllowCellular, AllowBattery, AllowCellularAndBattery.
#endregion
// We register the event handlers for the progress change
TransferRequest.TransferProgressChanged += Item.TransferProgressChanged;
// The BackgroundTransferRequest is ready to be addedd to the BackgroundTransferService queue.
// Before adding, we call the ITransferable BeforeAdding() method to perform additional
// operations (e.g. placing the file in the right folder).
Item.OnBeforeAdd();
// Now the BackgroundTrabsferRequest is ready to be added to the BackgroundTransferService queue
// A try/catch block is necessary to handle the possible exceptions
TransferRequest.TransferStatusChanged += new EventHandler<BackgroundTransferEventArgs>(TransferRequest_TransferStatusChanged); // Transfer manager handler for status change
try
{
BackgroundTransferService.Add(TransferRequest);
// If add was successful we can retrieve the RequestId value and store it in the ITransferable object
// The RequestId is generated right after the instantiation of the BackgroundTransferRequest, but to
// avoid overwriting a previous value on the ITransferable object, we store it only after "Add" is
// successful (which means that the same object is not currently transferring).
Item.RequestId = TransferRequest.RequestId;
// The BackgroundTransferRequest was successfully added to the BackgroundTransferService queue.
return true;
}
catch (BackgroundTransferInternalException ex)
{ //BackgroundTransferInternalException is thrown when:
// - The total request limit across all applications has been reached.
// - The HTTP network provider returned an error.
// - The HTTP network provider returned an error related to content-range request or response.
// - The HTTP network provider returned a network-related error.
// - The HTTP network provider returned a slow transfer error.
// - The isolated storage provider returned an error.
// In debug mode show MessageBox with exception details.
if (System.Diagnostics.Debugger.IsAttached)
{
MessageBox.Show("I'm unable to add the background transfer request (BackgroundTransferInternalException). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
}
}
catch (InvalidOperationException ex)
{ // InvalidOperationException is thrown when:
// - The request has already been submitted.
// - The maximum number of requests per application has been reached.
// - A request with the same DownloadLocation URI has already been submitted.
// - The user has disabled background tasks in the device’s Settings.
// In debug mode show MessageBox with exception details.
if (System.Diagnostics.Debugger.IsAttached)
{
MessageBox.Show("I'm unable to add the background transfer request (InvalidOperationException). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
}
}
catch (SystemException ex)
{ //SystemException is thrown when:
// - The maximum number of requests on the device has been reached.
// - The underlying transport layer returned an error.
// - The underlying transport layer returned an error related to the content-range request or response.
// In debug mode show MessageBox with exception details.
if (System.Diagnostics.Debugger.IsAttached)
{
MessageBox.Show("I'm unable to add the background transfer request (SystemException). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
}
}
catch (Exception ex)
{
// In debug mode show MessageBox with exception details.
if (System.Diagnostics.Debugger.IsAttached)
{
MessageBox.Show("I'm unable to add the background transfer request (Exception). " + ex.Message, "Unable to start transfer", MessageBoxButton.OK);
}
}
return false;
}
