void ClearClient()
{
_client.DownloadProgressChanged -= OnDownloadProgressChanged;
_client.DownloadFileCompleted -= OnDownloadFileCompleted;
_client.Dispose();
_client = null;
}
/// <summary>
/// 销毁对象，会停止所有的下载
/// </summary>
public void Dispose()
{
if (_client != null)
{
_client.DownloadProgressChanged -= OnDownloadProgressChanged;
_client.DownloadFileCompleted -= OnDownloadFileCompleted;
_client.CancelAsync();
_client.Dispose();
_client = null;
if (false == _isDone)
{
SetError("Canceled");
_isDone = true;
}
}
}