frmudpserver.frm

用WinSocket创建客户机服务器--UDP,为了写这个程序,花了我好长时间,无奈水平有限,是初学,请多指教

VERSION 5.00
Object = "{248DD890-BB45-11CF-9ABC-0080C7E7B78D}#1.0#0"; "MSWINSCK.OCX"
Begin VB.Form frmUDPServer 
   Caption         =   "Simple UDP Server"
   ClientHeight    =   3750
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   4710
   LinkTopic       =   "Form1"
   ScaleHeight     =   3750
   ScaleWidth      =   4710
   StartUpPosition =   3  'Windows Default
   Begin MSWinsockLib.Winsock udpServer 
      Left            =   2160
      Top             =   1680
      _ExtentX        =   741
      _ExtentY        =   741
      _Version        =   393216
      Protocol        =   1
   End
   Begin VB.TextBox txtOutput 
      Height          =   3375
      Left            =   0
      MultiLine       =   -1  'True
      ScrollBars      =   2  'Vertical
      TabIndex        =   2
      Top             =   360
      Width           =   4695
   End
   Begin VB.CommandButton cmdSend 
      Caption         =   "Send Text"
      Height          =   285
      Left            =   3480
      TabIndex        =   1
      Top             =   0
      Width           =   1215
   End
   Begin VB.TextBox txtSend 
      Height          =   285
      Left            =   0
      TabIndex        =   0
      Top             =   0
      Width           =   3375
   End
End
Attribute VB_Name = "frmUDPServer"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
' Fig. 19.15
' A simple server using UDP protocol
Option Explicit

Private Sub Form_Load()
   ' set up local port and wait for connection
   Call udpServer.Bind(5000)
End Sub

Private Sub Form_Terminate()
   Call udpServer.Close
End Sub

Private Sub Form_Resize()
   On Error Resume Next
   Call cmdSend.Move(ScaleWidth - cmdSend.Width, 0)
   Call txtSend.Move(0, 0, ScaleWidth - cmdSend.Width)
   Call txtOutput.Move(0, txtSend.Height, ScaleWidth, _
      ScaleHeight - txtSend.Height)
End Sub

Private Sub udpServer_DataArrival(ByVal bytesTotal As Long)
   Dim message As String
   Call udpServer.GetData(message)  ' get data from client
   txtOutput.Text = txtOutput.Text & _
      "From: IP address: " & udpServer.RemoteHostIP & _
      vbCrLf & "Port #: " & Str$(udpServer.RemotePort) & _
      vbCrLf & "Bytes received: " & Str$(bytesTotal) & _
      vbCrLf & "Message: " & message & vbCrLf & vbCrLf
   txtOutput.SelStart = Len(txtOutput.Text)
End Sub

Private Sub cmdSend_Click()
   Call udpServer.SendData(txtSend.Text)  ' send data to client
   txtOutput.Text = txtOutput.Text & _
      "Sent message: " & txtSend.Text & vbCrLf & vbCrLf
   txtSend.Text = ""
   txtOutput.SelStart = Len(txtOutput.Text)
   udpServer.RemotePort = 0
End Sub