为何无法触发mscomm事件请大家帮忙看看解决方案

为何无法触发mscomm事件请大家帮忙看看
我将pc两com口相连想通过如下程序实现通信.comsent用来向com1口发送数据,comreceive用来从com2口接收数据.但就是无法触发comreceive的oncomm事件,无法接收数据.请大家看看是怎么回事,是我这种方法根本无法实现啊,还是程序本身有问题,请大家指教
Private   Sub   cmdsent_Click()
Dim   strsent   As   String
strsent   =   Trim(txtsent.Text)
If   (strsent   =   " ")   Then
        MsgBox   "发送数据不能为空! ",   vbOKOnly,   "提示 "
        txtsent.SetFocus
Else
        comsent.Output   =   strsent
        MsgBox   "已经执行发送! ",   vbOKOnly,   "提示 "
End   If
End   Sub

Private   Sub   comreceive_OnComm()
      MsgBox   "收到数据！ "
      txtreceive.txt=comreceive.input
End   Sub

Private   Sub   Form_Activate()
  With   comsent
                    .InBufferSize   =   5120
                    .CommPort   =   1
                    .Settings   =   "4800,N,8,1 "
                    .InputLen   =   1
                    .InputMode   =   comInputModeText
                    .RThreshold   =   0
                    .PortOpen   =   True
    End   With
       
  With   comreceive
                    .InBufferSize   =   5120
                    .CommPort   =   2
                    .Settings   =   "4800,N,8,1 "
                    .InputLen   =   1
                    .InputMode   =   comInputModeText
                    .RThreshold   =   0
                    .PortOpen   =   True
End   With
End   Sub


------解决方案--------------------
你的代码中的
MsgBox "已经执行发送! ", vbOKOnly, "提示 "
语句中断了接收事件，应删除。
下列代码中改动2处，一是设置comreceive属性RThreshold为1，设置0则不触发OnComm时间中接收。二是不设置comreceive属性InputLen，以便有接收事件发生则全部接收。
Private Sub Form_Activate()
With comsent
.InBufferSize = 5120
.CommPort = 1
.Settings = "4800,N,8,1 "
.InputLen = 1
.InputMode = comInputModeText
.RThreshold = 0
.PortOpen = True
End With

With comreceive
.InBufferSize = 5120
.CommPort = 2
.Settings = "4800,N,8,1 "
'.InputLen = 1
.InputMode = comInputModeText
.RThreshold = 1
.PortOpen = True
End With
End Sub


------解决方案--------------------