/// <summary>
/// Asynchronously downloads file from the specified url to the specified path
/// </summary>
/// <param name="url"></param>
/// <param name="filePath"></param>
/// <param name="callback">A <see cref="DownloadImageCompletedCallback"/> to be invoked when the request is completed</param>
/// <param name="progressCallback"></param>
/// <returns></returns>
public object DownloadFileAsync(string url, string filePath, DownloadFileCompletedCallback callback, DownloadProgressChangedCallback progressCallback)
{
string urlValidationError;
if (!IsValidURL(url, out urlValidationError))
throw new ArgumentException(urlValidationError);
FileRequestAsyncState state = new FileRequestAsyncState(filePath, callback, progressCallback, DownloadFileAsyncCompleted);
HttpWebServiceRequest request = GetRequest();
request.GetResponseAsync(url, new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.None), IMAGE_ACCEPT, null, state);
return request;
}
/// <summary>
/// Asynchronously downloads file from the specified url to the specified path
/// </summary>
/// <param name="url"></param>
/// <param name="filePath"></param>
/// <param name="callback">A <see cref="DownloadImageCompletedCallback"/> to be invoked when the request is completed</param>
/// <param name="progressCallback"></param>
/// <returns></returns>
public object DownloadFileAsync(string url, string filePath, DownloadFileCompletedCallback callback, DownloadProgressChangedCallback progressCallback)
{
string urlValidationError;
if (!IsValidURL(url, out urlValidationError))
{
throw new ArgumentException(urlValidationError);
}
FileRequestAsyncState state = new FileRequestAsyncState(filePath, callback, progressCallback, DownloadFileAsyncCompleted);
HttpWebServiceRequest request = GetRequest();
request.GetResponseAsync(url, new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.None), IMAGE_ACCEPT, null, state);
return(request);
}
/// <summary>
/// Callback method for asynchronous requests
/// </summary>
private void DownloadFileAsyncCompleted(WebRequestAsyncState state)
{
FileRequestAsyncState requestState = (FileRequestAsyncState)state;
FileInfo fileResult = null;
if (!requestState.Request.Cancelled && requestState.Error == null)
{
try
{
fileResult = new FileInfo(requestState.FilePath);
}
catch (Exception ex)
{
requestState.Error = HttpWebServiceException.FileError(requestState.Request.BaseUrl, ex);
}
}
if (requestState.Request.ResponseStream != null)
{
requestState.Request.ResponseStream.Close();
}
requestState.DownloadFileCompleted(new DownloadFileAsyncResult(fileResult, requestState.Error, requestState.Request.Cancelled));
}