char* p = new char[500];
char& a = *p;
int l1 = sizeof(p); //4
int l2 = sizeof(a); //1
int l3 = sizeof(*p); //1
int l4 = strlen(p); //不固定 到'\0'为止
ZeroMemory(p, 500); //
int l5 = strlen(p); //0
char p2[500];
int l6 = sizeof(p2);//500