| description | title | ms.date | ms.topic | helpviewer_keywords | ms.assetid | |
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Learn more about: How to: Declare Interior Pointers with the const Keyword (C++/CLI) | How to: Declare Interior Pointers with the const Keyword (C++/CLI) | 10/12/2018 | reference |
| 64e08b0e-9396-4046-ab51-8f6588f32330 |
The following sample shows how to use const in the declaration of an interior pointer.
Important
This language feature is supported by the /clr compiler option, but not by the /ZW compiler option.
// interior_ptr_const.cpp// compile with: /clrusingnamespaceSystem; value structV { int i; }; ref structG { V v; String ^ msg; }; interior_ptr<int> f( interior_ptr<V> pv ) { return &(pv->i); } intmain() { int n = -1; int o = -1; interior_ptr<int> pn1 = &n; *pn1 = 50; V v; v.i = 101; V * npV = &v; // ok: &v yields a pointer to the native heap interior_ptr<int> pn2 = &n; interior_ptr<V> pV = &(v); pn2 = f(pV); *pn2 = 50; G ^pG = gcnew G; pV = &(pG->v); // ok: pV is an interior pointer interior_ptr<intconst> pn3 = &n; // *pn3 = 5; error because pn3 cannot be dereferenced and changed pn3 = &o; // OK, can change the memory location interior_ptr<int> const pn4 = &n; *pn4 = 5; // OK because you can dereference and change pn4// pn4 = &o; error cannot change the memory locationconst interior_ptr<constint> pn5 = &n; // *pn5 = 5; error cannot dereference and change pn5// pn5 = &o; error cannot change the memory locationconst G ^ h_G = gcnew G; // object is const, cannot modify any members of h_G or call any non-const methods// h_G->msg = "test"; error h_G is const interior_ptr<String^ const> int_ptr_G = &(h_G->msg); G ^ const h_G2 = gcnew G; // interior pointers to this object cannot be dereferenced and changed h_G2->msg = "test"; interior_ptr<String^ const> int_ptr_G2 = &(h_G->msg); };