C#调用C++DLL的两个函数，麻烦给看一下

Question

[DllImport("xxx.dll", CallingConvention= CallingConvention.Cdecl)]
static extern uint DecodeDataStream(
                                            ushort      msgId,       
                                            byte[]      msgData,     
                                            byte[]      decDataAdr,   
                                            int         dataSize,       
                                            byte[]       msgName       
                                    );void Test()
{
    byte[] decDataAdr = new byte[45] {0x24,0x00,/*...*/};
    byte[] tmpchar = new byte[100];
    byte[] msgData = tmpchar, msgName = tmpchar;
    uint a = DecodeDataStream(24, msgData, decDataAdr, 45, msgName);
}