请问各位，这是什么原因啊？？？？？？？

[phs520]

CSerialPortEx.h
public:
BYTE* m_szWriteBuffer;

CSerialPortEx.cpp
void CSerialPortEx::WriteToPort(BYTE* string,int nLength)
{
memset(m_szWriteBuffer,0,16);//!!!!!!!!1错
memcpy(m_szWriteBuffer,string,nLength);//!!!!!!!!1错
m_nToSend=nLength;
}

void CSerialPortEx::WriteToPort(CString str)
{
char *buffer=new char[20];
memset(buffer,0,20);
int nMaxLength=str.GetLength()+1
char *temp=str.GetBuffer(nMaxLength);
memcpy(buffer,temp,str.GetLength());
str.ReleaseBuffer();
BYTE* aaa="dfsdfs";
WriteToPort((BYTE*)buffer,str.GetLength());
}
提示错误："0x10218201"指令引用“0x00000000",该内存不能修改"written"：(m_szWriteBuffer)

[phs520]

为什么不能修改啊！！！！！！！！！！！该怎么做啊

[yym314]

you must malloc memory for m_szWriteBuffer.
m_szWriteBuffer = new BYTE[16];

[akiko]

m_szWriteBuffer使用之前new了没有啊

[phs520]

知道了各位，谢谢

[flyelf]

BYTE* m_szWriteBuffer;--->
BYTE m_szWriteBuffer[16];