IModelPropertyAccessor::SetValue method (dbgmodel.h)

Article
02/22/2024

The SetValue method is the setter for the property accessor. It is called whenever a client wishes to assign a value to the underlying property. Many properties are read-only. In such cases, calling the SetValue method will return E_NOTIMPL. Note that any caller which directly gets a property accessor is responsible for passing the key name and accurate instance object (this pointer) to the property accessor's SetValue method.

Syntax

HRESULT SetValue(
  PCWSTR       key,
  IModelObject *contextObject,
  IModelObject *value
);

Parameters

key

The name of the key to get a value for. A caller which fetches a property accessor directly is responsible for passing this accurately.

contextObject

The context object (instance this pointer) from which the property accessor was fetched.

value

The value to assign to the property.

Return value

This method returns HRESULT that indicates success or failure.

Remarks

Sample Code

class MyReadWriteProperty :
    public Microsoft::WRL::RuntimeClass<
        Microsoft::WRL::RuntimeClassFlags<
            Microsoft::WRL::RuntimeClassType::ClassicCom
            >,
        IModelPropertyAccessor
        >
{
public:

    IFACEMETHOD(GetValue)(_In_ PCWSTR /*pwszKey*/, 
                          _In_ IModelObject * /*pContextObject*/, 
                          _COM_Errorptr_ IModelObject **ppValue)
    {
        HRESULT hr = S_OK;
        *ppValue = nullptr;

        VARIANT vtValue;
        vtValue.vt = VT_I4;
        vtValue.lVal = m_value;
        
        ComPtr<IModelObject> spValue;
        hr = GetManager()->CreateIntrinsicObject(ObjectIntrinsic, &vtValue, &spValue);
        if (SUCCEEDED(hr))
        {
            *ppValue = spValue.Detach();
        }

        return hr;
    }

    IFACEMETHOD(SetValue)(_In_ PCWSTR /*pwszKey*/, 
                          _In_ IModelObject * /*pContextObject*/, 
                          _In_ IModelObject *pValue)
    {
        VARIANT vtValue;
        HRESULT hr = pValue->GetIntrinsicValueAs(VT_I4, &vtValue);
        if (SUCCEEDED(hr))
        {
            m_value = vtValue.lVal;
        }
        return S_OK;
    }

    HRESULT RuntimeClassInitialize(_In_ int value)
    {
        m_value = value;
        return S_OK;
    }

private:

    int m_value;
};

Requirements

Requirement	Value
Header	dbgmodel.h