尝试读取或写入受保护的内存。这通常指示其他内存已损坏?

Question

C#调用C++的dll
报错:
应用程序处于中断模式, 尝试读取或写入受保护的内存。这通常指示其他内存已损坏;

C++原型:

   void   GetTmpData(int type,BYTE * pbuff,float *maxtmp,int *maxx,int *maxy,float *mintmp,int *minx,int *miny,float *centertmp,float *tmparr,float *alltmp);

C#导入:

   [DllImport(@"XthermDll.dll" ,  CharSet = CharSet.Ansi),]
        public static extern void GetTmpData(int type, byte[] pbuff, ref float maxtmp, ref int  maxx,ref int maxy,ref float mintmp,ref int  minx,ref int  miny,ref float centertmp,ref float tmparr,ref float alltmp);

调用时:

    byte[] b = new byte[Buffer.Length];
                    float maxtmp = 0f;
                    int maxx = 0;
                    int maxy = 0;
                    float mintmp = 0f;
                    int minx = 0;
                    int miny = 0;
                    float centertmp = 0f;
                    float tmparr = 0f;
                    float alltmp = 0f;
                    GetTmpData(0, b, ref maxtmp, ref maxx, ref maxy, ref mintmp, ref minx, ref miny, ref centertmp, ref tmparr, ref alltmp);

各位大佬帮忙看看, 啥问题?感谢