可以通过HttpWebRequest的方式发送一个网络图片的请求，再通过HttpWebResponse接收返回的数据，，分析数据流得到图片的大小以及尺寸，代码如下：
/// <summary> /// 获取图片的大小和尺寸 /// </summary> /// <param>图片url</param> /// <param>图片大小</param> /// <param>图片尺寸</param> private void GetPhotoInfo(string aPhotoUrl, ref string aSize, ref string aLength) { try { Uri mUri = new Uri(aPhotoUrl); HttpWebRequest mRequest = (HttpWebRequest)WebRequest.Create(mUri); mRequest.Method = "GET"; mRequest.Timeout = 200; mRequest.ContentType = "text/html;charset=utf-8"; HttpWebResponse mResponse = (HttpWebResponse)mRequest.GetResponse(); Stream mStream = mResponse.GetResponseStream(); aSize = (mResponse.ContentLength / 1024).ToString() + "KB"; Image mImage = Image.FromStream(mStream); aLength = mImage.Width.ToString() + "x" + mImage.Height.ToString(); mStream.Close(); } catch (Exception e) { //MessageBox.Show(aPhotoUrl + "获取失败"); } }