private static void PrepareUpload(RestBase request, string path)
{
var startIndex = path.IndexOf("?status=", StringComparison.Ordinal) + 8;
var endIndex = path.IndexOf("&pic=", StringComparison.Ordinal);
request.Method = WebMethod.Post;
string status = path.Substring(startIndex, endIndex - startIndex);
request.AddField("status", status);
// https://upload.api.weibo.com/2/statuses/upload.json
startIndex = path.IndexOf("&pic=", StringComparison.Ordinal) + 5;
endIndex = path.Trim().Length;
var uri = path.Substring(startIndex, endIndex - startIndex);
path = path.Remove(path.IndexOf("?status="));
request.Path = path;
var file = new FileStream(Uri.UnescapeDataString(uri), FileMode.Open);
request.AddFile("pic", Path.GetFileName(Uri.UnescapeDataString(uri)), file, "image/jpeg");
}