我自己做的一个拨号小程序，小是小，可就是不能用。希望各位大哥，师姐们指点一下。谢谢！ 底下为程序代码： Option Explicit Dim lHandle As Long Private Sub Form_Load() Dim lResult As Long Call SendHand lResult = CloseHandle(lHandle) End Sub Private Function OpenThePort(cPort As String, cBaud As String, cParity As String, cData As String, cStop As String) As Boolean Dim lResult As Long Dim SECURITY As SECURITY_ATTRIBUTES Dim DCB_COMM As DCB Dim cDCBConfig As String Select Case cParity Case "NONE" cParity = "n" Case "EVEN" cParity = "e" Case "ODD" cParity = "e" End Select lHandle = CreateFile(cPort, GENERIC_READ Or GENERIC_WRITE, 0&, SECURITY, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, 0&) If lHandle = -1 Then '打开串口失败 OpenThePort = False MsgBox "串口可能正被其他应用程序占用！" lResult = CloseHandle(lHandle) Exit Function End If cDCBConfig = cBaud & "," & cParity & "," & cData & "," & cStop '设置DCB lResult = BuildCommDCB(cDCBConfig, DCB_COMM) '按用户设定配置一个DCB结构 If lResult = 0 Then OpenThePort = False MsgBox "无法建立DCB设备控制块" lResult = CloseHandle(lHandle) Exit Function End If lResult = SetCommState(lHandle, DCB_COMM) '实际设置一个串口的DCB If lResult = 0 Then OpenThePort = False MsgBox "无法建立DCB设备控制块" lResult = CloseHandle(lHandle) Exit Function End If OpenThePort = True 'lResult = CloseHandle(lHandle) End Function Private Sub SendHand() '发送握手信号的子过程 Dim Nchars As Long Dim Readbuff As String Dim Writebuff As String Dim lpDCB As DCB Dim lRet As Long Dim lpOverlapped As OVERLAPPED Dim RNum As Integer Dim Nlen As Long Dim Duration As Variant Call OpenThePort("COM2", "9600", "NONE", "8", "1") lRet = PurgeComm(lHandle, 1) '清输出缓冲区 lRet = PurgeComm(lHandle, 0) '清输入缓冲区 lRet = GetCommState(lHandle, lpDCB) '获得通讯口的状态 Shand: DoEvents Writebuff = "AT" + vbCr Nlen = Len(Writebuff) lRet = WriteFile(lHandle, Writebuff, Nlen, Nchars, lpOverlapped) '送握手信号入串口缓冲区 If lRet <= 0 Then MsgBox "发送操作出错,握手信号未发送成功", 16 'GoTo Shand '不成功则重发 End If 'Else 'GoTo Qtest 'End If 'GoTo Shand 'Qtest: Readbuff = "" '清除缓冲区为空 'Do While lHandle '循环查询串口 'RNum = 0 '设置读串口次数的指针为0 Duration = Timer + 5 Do DoEvents lRet = ReadFile(lHandle, Readbuff, 1, Nchars, lpOverlapped) If InStr(1, Readbuff, "OK") Then MsgBox "跟MODEM连接成功！" Exit Do End If Loop Until Timer >= Duration If Timer >= Duration Then MsgBox "跟MODEM连接失败！" Exit Sub End If Writebuff = "AT" + "13779936832" + vbCr Nlen = Len(Writebuff) lRet = WriteFile(lHandle, Writebuff, Nlen, Nchars, lpOverlapped) '送握手信号入串口缓冲区 Duration = Timer + 10 Do DoEvents lRet = ReadFile(lHandle, Readbuff, 1, Nchars, lpOverlapped) If InStr(1, Readbuff, "CONNECT") Then MsgBox "拨号成功！" Exit Do End If Loop Until Timer >= Duration If Timer >= Duration Then MsgBox "拨号失败！" Exit Sub End If End Sub