C＃中的WebResponse超时错误

Question

我正在尝试使用网络服务发送图片。我首先将图像转换为base64字符串并使用Web请求发送到服务器的Post方法。这是我的代码。

try
{
    qry = "Select ProductImage From tbl_Product where ProductOnlineID=0";
    dt = db.DataTable(qry);
    foreach (DataRow dr in dt.Rows)
    {
        string fileName = dr["ProductImage"].ToString();
        string storeLocation = Application.StartupPath + @"\product_image\";
        if (System.IO.File.Exists(storeLocation + fileName))
        {
            Image image = Image.FromFile(storeLocation + fileName);
            MemoryStream m = new MemoryStream();
            image.Save(m, image.RawFormat);
            byte[] imageBytes = m.ToArray();
            string base64String = Convert.ToBase64String(imageBytes);
            string url_upload_imag = @"http://Myserver/api/offline/json/1.0/index.php";
            string rq = "token=" + apikey + @"&json_data={%22method%22:%22uploadProductImagesLocal%22,%22data%22:[{%22imgName%22:%22" + fileName + "%22,%22imgString%22:%22" + base64String + "%22}]}";
            WebRequest request = WebRequest.Create(url_upload_imag);
            request.Method = "POST";
            request.ContentLength = rq.Length;
            byte[] array = new UTF8Encoding().GetBytes(rq);
            request.ContentType = "application/x-www-form-urlencoded";
            using (Stream str = request.GetRequestStream())
            {
                str.Write(array, 0, array.Length);
                using (WebResponse ws = request.GetResponse())
                {
                    DataContractJsonSerializer jsonSerializer = new DataContractJsonSerializer(typeof(RootObject_Image));
                    RootObject_Image obj = (RootObject_Image)jsonSerializer.ReadObject(ws.GetResponseStream());
                    MessageBox.Show("Done" + fileName + obj.data);
                }
            }
        }
    }
}
catch (WebException ex)
{
    MessageBox.Show("Error in Sending Image:" + ex.ToString(), "Error:", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
}

我的问题是..当我运行应用程序时，我得到超时错误..我已经尝试了将超时设置为无限的一切对我不起作用。我的base64字符串也是正确的。

Web服务是在php中创建的。什么可能是错误？如果有任何错误，可以是PHP或C＃？