MSComm接受到的二进制转换成十六进制显示的时候总少一个零

代码如下：

Private Sub Command1_Click()
MSComm1.PortOpen = True
MSComm1.Output = "a123456b"
Buf = ""
End Sub

Private Sub MSComm1_OnComm()
Select Case MSComm1.CommEvent
Case comEvReceive
InByte = MSComm1.Input
For i = LBound(InByte) To UBound(InByte)
Buf = Buf + Hex(InByte(i))
Next i
Text2.Text = Buf
MSComm1.PortOpen = False

Case comEvSend
MSComm1.Output = "a123465b"
Text1.Text = "传输缓冲区有 Sthreshold 个字符"
End Select

End Sub

小第是新手，那位大侠指导一下小第，不胜感激。。

StrWork = "Recv:" '把接收到的数据在文本框内显示
For j = LBound(Instring) To UBound(Instring)
StrWork = StrWork + " " + Format(Hex(Instring(j)), "00")
Next j
List2.AddItem StrWork