[RESOLVED] WideCharToMultiByte problem

[MikiSoft]

I'm facing a problem right now. Why this code below causes crash after executing CopyMemory?

Private Declare Function WideCharToMultiByte Lib "Kernel32.dll" ( _
    ByVal CodePage As Long, _
    ByVal dwFlags As Long, _
    ByVal lpWideCharStr As Long, _
    ByVal cchWideChar As Long, _
    ByVal lpMultiByteStr As Long, _
    ByVal cbMultiByte As Long, _
    ByVal lpDefaultChar As Long, _
    ByVal lpUsedDefaultChar As Long _
) As Long
 
Private Const CP_ACP        As Long = 0
 
Private Declare Function CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (ByVal _
        dest As Long, ByVal src As Long, ByVal Length As Long) As Long
 
Private Const BINARY_CHUNK As Long = 256
 
Private Function ToCPString(ByRef the_sValue As String) As Byte()
 
    Dim abytOutput()                As Byte
    Dim nValueLen                   As Long
    Dim nOutputByteLen              As Long
 
    ' Cache the input length.
    nValueLen = Len(the_sValue)
 
    ' See how big the output buffer will be.
    nOutputByteLen = WideCharToMultiByte(CP_ACP, 0&, StrPtr(the_sValue), nValueLen, 0&, 0&, 0&, 0&)
 
    If nOutputByteLen > 0 Then
        ' Resize output byte array to the size of the UTF-8 string.
        ReDim abytOutput(1 To nOutputByteLen)
 
        ' Make this API call again, this time giving a pointer to the output byte array.
        WideCharToMultiByte CP_ACP, 0&, StrPtr(the_sValue), nValueLen, VarPtr(abytOutput(1)), nOutputByteLen, 0&, 0&
    End If
 
    ' Return the array.
    ToCPString = abytOutput()
 
End Function
 
Private Sub CatBinary(bytData() As Byte, Bytes() As Byte)
    Dim BytesLen As Long, BinaryNext As Long
    
    BinaryNext = UBound(bytData) + 1
    BytesLen = UBound(Bytes) - LBound(Bytes) + 1
    If BinaryNext + BytesLen - 1 > BinaryNext Then
        If BytesLen > BINARY_CHUNK Then
            ReDim Preserve bytData(BinaryNext + BytesLen - 1)
        Else
            ReDim Preserve bytData(BinaryNext + BINARY_CHUNK - 1)
        End If
    End If
    CopyMemory bytData(BinaryNext), Bytes(LBound(Bytes)), BytesLen
End Sub
 
Private Sub CatBinaryString(bytData() As Byte, Text As String)
    Dim Bytes() As Byte
    
    Bytes = ToCPString(Text)
    CatBinary bytData, Bytes
End Sub
 
Private Sub TrimBinary(bytData() As Byte)
    If UBound(bytData) > 0 Then
        ReDim Preserve bytData(UBound(bytData) - 1)
    Else
        bytData = ""
    End If
End Sub
 
Sub Main()
Dim bytData() As Byte: bytData = ""
CatBinaryString bytData, "test"
MsgBox StrConv(bytData, vbUnicode)
End Sub