C#图片保存到本地

/// <summary>
/// 上传微信头像到服务器
/// </summary>
/// <param name="imgUrl"></param>
/// <param name="fileName"></param>
/// <returns></returns>
private bool UploadImgToServer(string imgUrl, string fileName)
{
bool isSuccess = false;
try
{
//检查文件夹是否存在
string mapPath = HttpContext.Current.Server.MapPath("~/Upload/HeadImg/");
if (!Directory.Exists(mapPath))
{
Directory.CreateDirectory(mapPath);
}
fileName = fileName + ".jpg";
string savePath = mapPath + fileName;
//检查文件是否已经存在，存在则删除后重新创建，保证头像最新并且一个用户只有一张图片储存在服务器
if (File.Exists(fileName))
{
File.Delete(fileName);
}
int timeOut = -1;
WebResponse response = null;
Stream stream = null;
try
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(imgUrl);
if (timeOut != -1) request.Timeout = timeOut;
response = request.GetResponse();
stream = response.GetResponseStream();
if (!response.ContentType.ToLower().StartsWith("text/"))
isSuccess = SaveBinaryFile(response, savePath);
}
finally
{
if (stream != null) stream.Close();
if (response != null) response.Close();
}
}
catch (Exception)
{
isSuccess = false;
}

return isSuccess;
}

private bool SaveBinaryFile(WebResponse response, string savePath)
{
bool value = false;
byte[] buffer = new byte[1024];
Stream outStream = null;
Stream inStream = null;
try
{
if (File.Exists(savePath)) File.Delete(savePath);
outStream = System.IO.File.Create(savePath);
inStream = response.GetResponseStream();
int l;
do
{
l = inStream.Read(buffer, 0, buffer.Length);
if (l > 0) outStream.Write(buffer, 0, l);
} while (l > 0);
value = true;
}
finally
{
if (outStream != null) outStream.Close();
if (inStream != null) inStream.Close();
}
return value;
}