索引超出数组界限

[andymdj]

Dim SendData(3) As Byte
Dim ReceiveData(255) As Byte
Dim i As Integer


If AxMSComm1.PortOpen = True Then
'On Error GoTo ErrorHandler
SendData(0) = &H84
SendData(1) = &H1E
SendData(2) = &HCC
SendData(3) = &H91
AxMSComm1.Output = SendData
AxMSComm1.InBufferCount = 0 '清空接收缓冲区
AxMSComm1.InputLen = 2
'AxMSComm1.RThreshold = 1
ReceiveData = AxMSComm1.Input

If ReceiveData(0) = &HF1 Then -----这里为什么报索引超出数组界限的错误

[jane_zhao]

在取ReceiveData(0)时,应判断是否为nothing,
If ReceiveData isnot nothing andalso ReceiveData(0) = &HF1 Then

[EnForGrass]

[Quote=引用楼主 andymdj 的回复:]
Dim SendData(3) As Byte
Dim ReceiveData(255) As Byte
Dim i As Integer


If AxMSComm1.PortOpen = True Then
'On Error GoTo ErrorHandler
Sen……
[/Quote]
看不出来，自己仔细调试

[bdmh]

断点，看看ReceiveData有没有数据

[porschev]

看看ReceiveData里是什么

[JianDom]

ReceiveData = AxMSComm1.Input
ReceiveData已重新赋值,AxMSComm1.Input这里可能为空

[l_g_guo]

问题应该在这句上：
ReceiveData = AxMSComm1.Input

检查AxMSComm1.Input里面有什么东东，是否为数组？

[music_0000]

4楼是对的