Coding for WMI

From:

one-trick-pony <worldofpain.aamir@gmail.com>

Newsgroups:

microsoft.public.vc.language

Date:

Tue, 12 Jun 2007 05:48:56 -0700

Message-ID:

<1181652536.216668.241890@g37g2000prf.googlegroups.com>

Greetings,

I am trying to use WMI to interact with network configuration for
Windows XP. My challenge is constructing C/C++ code. I have part of
the solution but I am getting an error message. Below is my initial
attempt at code in C++:

// set up to call the Win32_NetworkAdapterConfiguration::EnableDHCP
method

//EnableDHCP takes no parameters or arguments.
BSTR MethodName = SysAllocString(L"EnableDHCP");
BSTR ClassName =
SysAllocString(L"Win32_NetworkAdapterConfiguration");

IWbemClassObject* pClass = NULL;
hres = pWbemServices->GetObject(ClassName, 0, NULL, &pClass,NULL);

IWbemClassObject* pInParamsDefinition = NULL;
hres = pClass->GetMethod(MethodName, 0,
        NULL, NULL);

// I don't understand why these two lines of code are needed?
IWbemClassObject* pClassInstance = NULL;
hres = pInParamsDefinition->SpawnInstance(0, &pClassInstance);

    // Execute Method

    hres = pWbemServices->ExecMethod(ClassName, MethodName, 0,
    NULL, NULL, NULL, NULL);

    if (FAILED(hres))
    {

                switch (hres){
                case WBEM_E_FAILED:
                        AfxMessageBox("1");
                        break;
                case WBEM_E_INVALID_CLASS:
                        AfxMessageBox("2");
                        break;
                case WBEM_E_INVALID_PARAMETER:
                        AfxMessageBox("3");
                        break;
                case WBEM_E_METHOD_DISABLED:
                        AfxMessageBox("4");
                        break;
                case WBEM_E_METHOD_NOT_IMPLEMENTED:
                        AfxMessageBox("5");
                        break;
                case WBEM_E_NOT_FOUND:
                        AfxMessageBox("6");
                        break;
                case WBEM_E_PROVIDER_NOT_CAPABLE:
                        AfxMessageBox("7");
                        break;
                case WBEM_E_INVALID_METHOD:
                        AfxMessageBox("8");
                        break;
                case WBEM_E_INVALID_METHOD_PARAMETERS:
                        AfxMessageBox("9"); << This Error Message
pops up.
                        break;
                case WBEM_E_TRANSPORT_FAILURE:
                        AfxMessageBox("10");
                        break;
                case WBEM_E_ACCESS_DENIED:
                        AfxMessageBox("11");
                        break;

                }
    }

This is part of code and my defined error message number that pops up
is 9. At MSDN it states,

This error results from one of two causes:
The supplied pInParams object was determined by the provider to be
invalid.

The strObjPath parameter specifies a class without the [static]
qualifier on the method.

Since "EnableDHCP" method takes no parameters-why is this message
popping up? Furthermore, I do not know how to tell my code to select
an adapter-that is, for which adapter is it issuing "EnableDHCP"
for? I suspect my code is missing pieces within above piece of
code. Need help.