下载（打开）PDF文件 代码

网上的代码很多，但现在大多数都是Framework 3.5的啦，对于2.0，2.5有的方法不是很兼容，花了半个小时才找到一个合适，现在记录如下：

注意：不适合网络路径，只适合本地文件， 网络路径请参考我另一篇Blog

public void DownloadFile(string strFileNamePath)
{
long chunkSize = 102400;
byte[] buffer = new byte[chunkSize];
//long dataToRead=0;
FileStream stream = null;
try
{
FileInfo info = new FileInfo(strFileNamePath);
Response.Clear();
stream = new FileStream(strFileNamePath, FileMode.Open, FileAccess.Read, FileShare.Read);
Response.Clear();
Response.AddHeader("Content-Length", stream.Length.ToString());
Response.ContentType = "application/pdf";
long fileLength = stream.Length;
int size = 10240;//10K一--分块下载，10K为1块
byte[] readData = new byte[size];
if (size > fileLength)
size = Convert.ToInt32(fileLength);
long fPos = 0;
bool isEnd = false;
while (!isEnd)
{
if ((fPos + size) >= fileLength)
{
size = Convert.ToInt32(fileLength - fPos);
isEnd = true;
}
readData = new byte[size];
stream.Position = fPos;
stream.Read(readData, 0, size);
Response.BinaryWrite(readData);
Response.OutputStream.Flush();
fPos += size;
}
stream.Close();
Response.OutputStream.Close();
Response.End();//非常重要，没有这句的话，页面的HTML代码将会保存到文件中
Response.Close();
}
catch (Exception)
{
if (stream != null)
{
stream.Close();
stream = null;
}
}

}