VB.net TCP 是如何发送文件的 , 给一个示例

下面是一个简单的 VB.NET TCP 发送文件的示例：

' 客户端发送文件
Private Sub SendFile(ByVal filePath As String)
    Try
        ' 创建 TCP 客户端
        Dim client As New TcpClient("127.0.0.1", 8888)
        ' 打开文件流
        Dim fileStream As New FileStream(filePath, FileMode.Open, FileAccess.Read)
        ' 获取文件名
        Dim fileName As String = Path.GetFileName(filePath)
        ' 创建写入器
        Dim writer As New BinaryWriter(client.GetStream())
        ' 发送文件名
        writer.Write(fileName)
        ' 发送文件长度
        writer.Write(fileStream.Length)
        ' 发送文件内容
        Dim buffer(4096) As Byte
        Dim bytesRead As Integer
        Do
            bytesRead = fileStream.Read(buffer, 0, buffer.Length)
            If bytesRead > 0 Then
                writer.Write(buffer, 0, bytesRead)
            End If
        Loop While bytesRead > 0
        ' 关闭流和连接
        fileStream.Close()
        writer.Close()
        client.Close()
    Catch ex As Exception
        Console.WriteLine(ex.Message)
    End Try
End Sub

' 服务器接收文件
Private Sub ReceiveFile()
    Try
        ' 创建 TCP 服务器
        Dim server As TcpListener = New TcpListener(IPAddress.Any, 8888)
        server.Start()
        Console.WriteLine("等待客户端连接...")
        ' 接受客户端连接
        Dim client As TcpClient = server.AcceptTcpClient()
        Console.WriteLine("客户端已连接...")
        ' 创建读取器
        Dim reader As New BinaryReader(client.GetStream())
        ' 读取文件名
        Dim fileName As String = reader.ReadString()
        ' 读取文件长度
        Dim fileLength As Long = reader.ReadInt64()
        ' 创建文件流
        Dim fileStream As New FileStream(fileName, FileMode.Create, FileAccess.Write)
        ' 读取文件内容
        Dim buffer(4096) As Byte
        Dim bytesRead As Integer
        Do
            bytesRead = reader.Read(buffer, 0, buffer.Length)
            If bytesRead > 0 Then
                fileStream.Write(buffer, 0, bytesRead)
            End If
        Loop While bytesRead > 0
        ' 关闭流和连接
        fileStream.Close()
        reader.Close()
        client.Close()
        server.Stop()
        Console.WriteLine("文件接收完毕。")
    Catch ex As Exception
        Console.WriteLine(ex.Message)
    End Try
End Sub

在此示例中，客户端首先连接到服务器，然后将文件名、文件长度和文件内容依次发送给服务器。服务器接收到数据后，创建文件并将文件内容写入文件中，最后关闭连接。