serialport事件触发方式

1、Public Class Form1 Dim mSTR As String Dim strData As String Dim strDat As String 'Dim mSize1 As Integer Dim mRecvByte() As Byte Dim Hexsj As String Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e AsHandles SerialPort1.DataReceived Dim mSize As Integer = Me.SerialPort1.BytesT

2、oRead 'mSize1 = mSize ReDim mRecvByte(mSize - 1) SerialPort1.Read(mRecvByte, 0, mSize) BeginInvoke(New EventHandler(AddressOf ONMLoadA), SerialPort1.BytesToRead() '使用委托方式显示接收到的字符串 End Sub Sub ONMLoadA(ByVal sender As System.Object, ByVal e As System.EventArgs) '委托 'TextBox4.Text = mS

3、TR Dim i As Integer For i = 0 To UBound(mRecvByte) 'mSize - 1 strData = strData & IIf(mRecvByte(i) > 15, Hex(mRecvByte(i), "0" & Hex(mRecvByte(i) Next Dim sj As Byte For i = 1 To Len(strData) Step 2 '处理为ASCII字符 sj = Val("&H" & Mid(strData, i, 2) If sj &

4、lt; 32 Or sj > 128 Then '当接收字节中有Chr(0)时，其后字符被切割 strDat = strDat & "." Else strDat = strDat & Chr(sj) End If Next TextBox1.Text = strDat '显示字符 TextBox2.Text = strData '显示为进制 TextBox3.Text = Len(strData) / 2 End Sub Private Sub Form1_Load(ByVal sender As System.Object,

5、 ByVal e As System.EventArgs) Handles MyBase.Load SerialPort1.BaudRate = 9600 '波特率设为 SerialPort1.PortName = "com1" '端口为串口 If SerialPort1.IsOpen = False Then SerialPort1.Open() '打开串口 Hexsj = TxtSend.Text = Hexsj End Sub Private Sub Button1_Click(ByVal sender As System.Object, By

6、Val e As System.EventArgs) Handles Button1.Click strData = "" strDat = "" TextBox1.Text = "" TextBox2.Text = "" TextBox3.Text = "" End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim

7、 bytHex() As Byte ReDim bytHex(Len(Hexsj) 2) - 1) Dim i As Integer For i = 1 To Len(Hexsj) Step 2 bytHex(i - 1) / 2) = Val("&H" & Mid(Hexsj, i, 2) Next SerialPort1.Write(bytHex, 0, bytHex.Length) End SubEnd ClassPrivate Sub Form1_Load(ByVal sender As Object, ByVal e As System.Event

8、Args) Handles Me.Load  Dim port As SerialPort = New SerialPort("COM4", 9600, Parity.Even, 8, StopBits.One)  port.Open()  port.DtrEnable = True  port.RtsEnable = True  port.ReceivedBytesThreshold = 64  End Sub当你需要接收到几个字符触发一次DataReceived的时候，ReceivedBytesThreshold就设置为几你设置的接收长度不对吧，你设置为1试试不就知道了嘛设置为port.ReceivedBytesThreshold =1也测试过了，也不能触发。之前用另一种方式，数据传送没有问题(用串口助手测试的)现在，只是form画面打开了，只是不触发Seri