多窗体共用一个串口接收事件应该如何编写

Question

目前做一个上位机软件，主窗体FrmMain的pannel控件加载两个子窗体FrmCOM和FrmMotor，两个在子窗体共用一个主窗体的串口。两个子窗体通过按键切换。
主窗体(FrmMain)：
public static SerialPort serialportcom = new SerialPort();
子窗体都分别创建了接收数据事件：
子窗体FrmCOM：
FrmMain.serialportcom.DataReceived += new SerialDataReceivedEventHandler(serialportcom_DataReceived1);
public void serialportcom_DataReceived1(object sender, SerialDataReceivedEventArgs e)
子窗体FrmMotor：
FrmMain.serialportcom.DataReceived += new SerialDataReceivedEventHandler(serialportcom_DataReceived2);
public void serialportcom_DataReceived2(object sender, SerialDataReceivedEventArgs e)
感觉两个接收事件产生冲突，无论哪个子窗体，都无法接收到数据，屏蔽其中一个，另一个就接收正常。
请教各位，哪里存在的问题？多窗体共用一个串口接收事件应该如何编写？
我考虑加载其中一个窗体注销另外一个事件，如下：
子窗体FrmCOM：
FrmMain.serialportcom.DataReceived += new SerialDataReceivedEventHandler(serialportcom_DataReceived1);
FrmMain.serialportcom.DataReceived -= new SerialDataReceivedEventHandler(serialportcom_DataReceived2);
public void serialportcom_DataReceived1(object sender, SerialDataReceivedEventArgs e)
子窗体FrmMotor：
FrmMain.serialportcom.DataReceived += new SerialDataReceivedEventHandler(serialportcom_DataReceived2);
FrmMain.serialportcom.DataReceived -= new SerialDataReceivedEventHandler(serialportcom_DataReceived1);
public void serialportcom_DataReceived2(object sender, SerialDataReceivedEventArgs e)
还是不行，谢谢大家，急。

Answer 1

一个窗口这里处理串口数据接收事件，收到时通过其他方式传递给另一个窗口，比如SendMessage之类的方法