【求助】C# Socket 编程 求救 为什么此程序 文件传输时会有大小限制？

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Net; using System.Net.Sockets; using System.IO; namespace File { public partial class FileTrans : Form { public FileTrans() { InitializeComponent(); } private void SelectBtn_Click(object sender, EventArgs e) { Ofd.ShowDialog(); SelectBox.Text = Ofd.FileName; } private void SendBtn_Click(object sender, EventArgs e) { //tcp.Start(); String path = SelectBox.Text; TcpClient client = new TcpClient(); try { client.Connect(IPAddress.Parse(IPBox.Text), 5000); MsgBox.AppendText("连接成功！"); } catch (Exception E) { MsgBox.AppendText(E.Message); } FileStream file = new FileStream(path,FileMode.Open,FileAccess.Read); NetworkStream stream = client.GetStream(); byte[] by = new byte [2048]; int data; while ((data = file.Read(by, 0, 2048)) != 0) { stream.Write(by,0,by.Length);//发送文件到目标机器 stream.Flush(); by = new byte[2048]; } client.Client.Shutdown(SocketShutdown.Both); stream.Close(); file.Close(); MsgBox.AppendText("/n发送文件" + Ofd.FileName); } private void Receive_Click(object sender, EventArgs e) { Sfd.ShowDialog(); String path = Sfd.FileName; TcpClient client = tcp.AcceptTcpClient(); FileStream fs = new FileStream(path,FileMode.OpenOrCreate,FileAccess.Write); NetworkStream stream = client.GetStream(); int count; byte[] by = new byte[2048]; while ((count = stream.Read(by,0,by.Length)) != 0) { fs.Write(by, 0, count); stream.Flush(); by = new byte[2048]; } stream.Close(); fs.Close(); //sock.Close(); MsgBox.AppendText("/n接受成功"); } TcpListener tcp = null; private void FileTrans_Load(object sender, EventArgs e) { tcp = new TcpListener(5000); tcp.Start(); } } }

为什么此段代码  会有文件大小限制 ？

while ((data = file.Read(by, 0, 2048)) != 0) { stream.Write(by,0,by.Length);//发送文件到目标机器 stream.Flush(); by = new byte[2048]; }

不是应该循环读文件流么？   求大侠指教。。。