读写流我把byte数组长度设置成1000或2000时得到的文件总出错

Question

        private string down(string inUrl,string title)
        {
            //以字符流的形式下载文件      
 
            WebRequest objRequest = System.Net.HttpWebRequest.Create(inUrl);
            try
            {
                BufferedStream buff = new BufferedStream(objRequest.GetResponse().GetResponseStream());                byte[] bytes = new byte[1024];//这里如果是1000或2000时有时得到的文件（大小5-6M左右）出错有时不出错                FileStream fs2 = new FileStream(title, FileMode.Create, FileAccess.Write);
                BufferedStream bs2 = new BufferedStream(fs2);                while (buff.Read(bytes, 0, bytes.Length) > 0)
                {
                    //  buff.Read(bytes, 0, bytes.Length);
                    int aa = bytes.Length;                    bs2.Write(bytes, 0, bytes.Length);
                    bs2.Flush();
                }                buff.Close();
                bs2.Close();
                fs2.Close();
            }
            catch
            {
                title = "123";
            }
            return title;
        }

Answer 1

int aa = bytes.Length;bs2.Write(bytes, 0, bytes.Length);就这两句出错，bytes.Length永远是你上面设定的固定值。而实际并不一定读取恰好等于数组长度的字节数。应该设定个表示实际读取的字节数的变量
int readByteNum;
while ((readByteNum = buff.Read(bytes, 0, bytes.Length)) > 0)
  {  bs2.Write(bytes, 0, readByteNum);
  bs2.Flush();
  }