如何调试解决方案中包含的不受管理的C ++代码

Question

I am using a third-party, proprietary DLL for which the source code is not available to me. Wrapper code that appears to have been auto-generated using SWIG 1.3.39 is, however, available to me. The wrapper code consists of a C++ file that compiles (using some headers that describe the DLL) to a DLL and of a C# project that makes PInvoke calls to the C++ wrapper DLL.

Those C++ projects I have included in my project Solution , however when I set the break point in the C++ code , I never get there. When I try to F11 in my C#, to go inside the C++ function , I get "Show Assembly" instead.

I have trie Solution > Proporties > Configuration Proporties but don't find anything with the option to debug Unmanaged/Native Code.

Edit

The wrapper C++ code is available to me and I need to see the values I am passing from C# are actually getting passed to the C# code .

// In one file of the C# wrapper:
public string GetKey()
{
    // swigCPtr is a HandleRef to an object already created
    string ret = csWrapperPINVOKE.mdMUHybrid_GetKey(swigCPtr);
    return ret;
}

// In the csWrapperPINVOKE class in another file in the C# wrapper:
[DllImport("csWrapper.dll", EntryPoint="CSharp_mdMUHybrid_GetKey")]
public static extern StringBuilder mdMUHybrid_GetKey(HandleRef jarg1);

And the C++ code from the C++ wrapper .

SWIGEXPORT char * SWIGSTDCALL CSharp_mdMUHybrid_GetKey(void * jarg1) {
  char * jresult ;
  mdMUHybrid *arg1 = (mdMUHybrid *) 0 ;
  char *result = 0 ;

  arg1 = (mdMUHybrid *)jarg1; 
  result = (char *)(arg1)->GetKey();
  jresult = SWIG_csharp_string_callback((const char *)result); 
  return jresult;
}

Now As I am trying to pass swigCPtr from the C# wrapper by using csWrapperPINVOKE.mdMUHybrid_GetKey(swigCPtr);

Now I want to see if jarg1 is getting the value from swigCPtr;

SWIGEXPORT char * SWIGSTDCALL CSharp_mdMUHybrid_GetKey(void * jarg1) {
  char * jresult ;
  mdMUHybrid *arg1 = (mdMUHybrid *) 0 ;
  char *result = 0 ;

  arg1 = (mdMUHybrid *)jarg1; 
  result = (char *)(arg1)->GetKey();
  jresult = SWIG_csharp_string_callback((const char *)result); 
  return jresult;
}

Answer 1

When you have a managed exe and want to debug the native DLL it uses you need to tell the debugger about that. Don't use the Debugger Type Auto , what's the default. Use Mixed instaed.

The auto will identify the managed exe and allowes managed debugging. That's not what you need to debug native C++ code.

You find the Debugger Type setting in the Debugging section of the project properties.