Notitie
Voor toegang tot deze pagina is autorisatie vereist. U kunt proberen u aan te melden of de directory te wijzigen.
Voor toegang tot deze pagina is autorisatie vereist. U kunt proberen de mappen te wijzigen.
Belangrijk
In Visual Studio 2015 wordt deze manier om expressie-evaluators te implementeren afgeschaft. Zie clr-expressie-evaluators en voorbeeld van beheerde expressie-evaluator voor informatie over het implementeren van CLR-expressie-evaluators.
Om de waarde van een lokaal te verkrijgen, roept Visual Studio GetPropertyInfo voor die lokale aan. In deze implementatie implementeert de klasse CFieldProperty de IDebugProperty2-interface voor elke lokale.
Deze implementatie van IDebugProperty2::GetPropertyInfo voert de volgende taken uit:
Haalt de lokale naam, eigenschap en kenmerken op uit de FIELD_INFO-structuur die is gevuld toen de klasse werd geïnstantieerd en geïnitialiseerd.
Hiermee wordt het lokale type opgehaald uit het object IDebugField .
Haalt de lokale waarde van het
IDebugFieldobject op. Dit veld is gebonden aan de geheugenlocatie van de lokale met behulp van het IDebugBinder-object en de waarde wordt verkregen van het resulterende IDebugObject-object .Retourneert alle aangevraagde eigenschappen in een DEBUG_PROPERTY_INFO structuur.
Beheerde code
In dit voorbeeld ziet u een implementatie van IDebugProperty2::GetPropertyInfo voor een lokaal van een methode in beheerde code. Er wordt ook een helperfunctie weergegeven, Field.GetTypedie wordt gebruikt om het veldtype op te halen.
Field.GetValue wordt weergegeven in Evaluate locals. Met de helperfunctie Field.MapModifiersToAttributes (niet weergegeven) worden de FIELD_MODIFIERS vlaggen van een veld geconverteerd naar DBG_ATTRIB_FLAGS waarden.
namespace EEMC
{
public class CFieldProperty : IDebugProperty2
{
public HRESULT GetPropertyInfo(
uint dwFields,
uint radix,
uint timeout,
IDebugReference2[] refArgs,
uint argCount,
DEBUG_PROPERTY_INFO[] infoArray)
{
DEBUGPROP_INFO_FLAGS flags = (DEBUGPROP_INFO_FLAGS) dwFields;
DEBUGPROP_INFO_FLAGS infoFields = DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_NONE;
// Initialize the structure.
DEBUG_PROPERTY_INFO info = infoArray[0];
info.pProperty = null;
// Fill in the full name, if requested.
if (0 != (flags & DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_FULLNAME))
{
info.bstrFullName = fieldInfo.bstrFullName;
infoFields |= DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_FULLNAME;
}
// Fill in the name, if requested.
if (0 != (flags & DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_NAME))
{
info.bstrName = fieldInfo.bstrName;
infoFields |= DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_NAME;
}
// Fill in the type, if requested.
if (0 != (flags & DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_TYPE))
{
if (fieldType == null)
fieldType = Field.GetType(field, out fieldSize);
if (fieldType == null)
info.bstrType = "unknown";
else
info.bstrType = fieldType.ToString();
infoFields |= DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_TYPE;
}
// The property associated with this property is this property.
if (0 != (flags & DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_PROP))
{
info.pProperty = this;
infoFields |= DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_PROP;
}
// Get the property value, if requested.
if (0 != (flags & DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_VALUE))
{
if (fieldType == null)
fieldType = Field.GetType(field, out fieldSize);
if (fieldType == null)
info.bstrValue = "?";
else
{
object o = Field.GetValue(binder, field, fieldType, fieldSize);
if (o == null)
info.bstrValue = "?";
else
info.bstrValue = o.ToString();
}
infoFields |= DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_VALUE;
}
// Get the property attributes, if requested.
if (0 != (flags & DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_ATTRIB))
{
info.dwAttrib =
(ulong) Field.MapModifiersToAttributes(
(FIELD_MODIFIERS) fieldInfo.dwModifiers,
fieldKind);
infoFields |= DEBUGPROP_INFO_FLAGS.DEBUGPROP_INFO_ATTRIB;
}
info.dwFields = (uint) infoFields;
infoArray[0] = info;
return COM.S_OK;
}
}
//----------------------------------------------------------------------------
internal class Field
{
internal static Type GetType(IDebugField field, out uint size)
{
size = 0;
IDebugField fieldType = null;
field.GetType(out fieldType);
if (fieldType == null) return null;
// Get field size.
fieldType.GetSize(out size);
// Get approximate type name.
FIELD_INFO[] fieldTypeInfo = new FIELD_INFO[1];
fieldType.GetInfo((uint) FIELD_INFO_FIELDS.FIF_NAME,
fieldTypeInfo);
// Map approximate name to type name.
switch (fieldTypeInfo[0].bstrName)
{
case "whole":
switch (size)
{
case 1: return typeof(sbyte);
case 2: return typeof(short);
case 4: return typeof(int);
case 8: return typeof(long);
}
break;
case "uwhole":
switch (size)
{
case 1: return typeof(byte);
case 2: return typeof(char);
case 4: return typeof(uint);
case 8: return typeof(ulong);
}
break;
case "real":
switch (size)
{
case 4: return typeof(float);
case 8: return typeof(double);
}
break;
case "bool": return typeof(bool);
case "string": return typeof(string);
}
return null;
}
}
Onbeheerde code
In dit voorbeeld ziet u een implementatie van IDebugProperty2::GetPropertyInfo voor een lokale variabele van een methode in onbeheerde code. Er worden ook twee helperfuncties weergegeven en FieldGetTypeFieldGetValue die worden gebruikt om respectievelijk het type en de waarde van het veld op te halen. De VARIANTs worden gebruikt voor de waarde en het type van het veld, omdat VARIANT een breed scala aan waardetypen kan verwerken. In deze implementatie retourneert FieldGetValue een IDebugField-object, dat later wordt omgezet in een waarde binnen een aanroep naar FieldGetPrimitiveValue (zoals weergegeven in Evaluate locals).
STDMETHODIMP CFieldProperty::GetPropertyInfo(
in DEBUGPROP_INFO_FLAGS infoFlags,
in DWORD radix,
in DWORD timeout,
in IDebugReference2** ppargs,
in DWORD argCount,
out DEBUG_PROPERTY_INFO* ppropertyInfo
)
{
if (!ppropertyInfo)
return E_INVALIDARG;
else
memset(ppropertyInfo,0,sizeof(*ppropertyInfo));
if (infoFlags & DEBUGPROP_INFO_FULLNAME)
{
ppropertyInfo->dwFields |= DEBUGPROP_INFO_FULLNAME;
ppropertyInfo->bstrFullName = SysAllocString( m_fieldInfo.bstrFullName );
}
if (infoFlags & DEBUGPROP_INFO_NAME)
{
ppropertyInfo->dwFields |= DEBUGPROP_INFO_NAME;
ppropertyInfo->bstrName = SysAllocString( m_fieldInfo.bstrName );
}
if (infoFlags & DEBUGPROP_INFO_TYPE)
{
ppropertyInfo->dwFields |= DEBUGPROP_INFO_TYPE;
VARIANT type;
if (SUCCEEDED(FieldGetType( m_field, &type )))
{
// Convert the variant's type to a string
VariantTypeToString( type, &(ppropertyInfo->bstrType) );
VariantClear(&type);
}
if (ppropertyInfo->bstrType == NULL)
ppropertyInfo->bstrType = SysAllocString( GetString(IDS_MSG_UNKNOWNTYPE) );
}
if (infoFlags & DEBUGPROP_INFO_PROP)
{
ppropertyInfo->dwFields |= DEBUGPROP_INFO_PROP;
QueryInterface( IID_IDebugProperty2,
reinterpret_cast<void**>(&(ppropertyInfo->pProperty)) );
}
if (infoFlags & DEBUGPROP_INFO_VALUE)
{
ppropertyInfo->dwFields |= DEBUGPROP_INFO_VALUE;
//only show primitive values
VARIANT value;
if (SUCCEEDED(FieldGetValue(m_field, &value)))
{
VariantValueToString( radix, m_binder, value,
&(ppropertyInfo->bstrValue) );
VariantClear(&value);
}
if (ppropertyInfo->bstrValue == NULL)
ppropertyInfo->bstrValue = SysAllocString( GetString(IDS_MSG_UNKNOWNVALUE) );
}
if (infoFlags & DEBUGPROP_INFO_VALUE_AUTOEXPAND)
{
// AUTOEXPAND is ignored in this example
}
if (infoFlags & DEBUGPROP_INFO_ATTRIB)
{
ppropertyInfo->dwFields |= DEBUGPROP_INFO_ATTRIB;
FIELD_MODIFIERS modifiers = m_fieldInfo.dwModifiers;
DBG_ATTRIB_FLAGS attrib = DBG_ATTRIB_NONE;
//access
if (modifiers & FIELD_MOD_ACCESS_PUBLIC)
attrib |= DBG_ATTRIB_ACCESS_PUBLIC;
if (modifiers & FIELD_MOD_ACCESS_PRIVATE)
attrib |= DBG_ATTRIB_ACCESS_PRIVATE;
if (modifiers & FIELD_MOD_ACCESS_PROTECTED)
attrib |= DBG_ATTRIB_ACCESS_PROTECTED;
if (modifiers & FIELD_MOD_FINAL)
attrib |= DBG_ATTRIB_ACCESS_FINAL;
//constant
if (modifiers & FIELD_MOD_CONSTANT)
attrib |= DBG_ATTRIB_VALUE_READONLY;
//storage
if (m_fieldKind & FIELD_SYM_GLOBAL)
attrib |= DBG_ATTRIB_STORAGE_GLOBAL;
if (modifiers & FIELD_MOD_STATIC)
attrib |= DBG_ATTRIB_STORAGE_STATIC;
//type modifier
if (modifiers & FIELD_MOD_VIRTUAL)
attrib |= DBG_ATTRIB_TYPE_VIRTUAL;
if (modifiers & FIELD_MOD_CONSTANT)
attrib |= DBG_ATTRIB_TYPE_CONSTANT;
if (modifiers & FIELD_MOD_SYNCHRONIZED)
attrib |= DBG_ATTRIB_TYPE_SYNCHRONIZED;
if (modifiers & FIELD_MOD_VOLATILE)
attrib |= DBG_ATTRIB_TYPE_VOLATILE;
//type
if (m_fieldKind & FIELD_TYPE_METHOD)
attrib |= DBG_ATTRIB_METHOD;
if (m_fieldKind & FIELD_TYPE_PROP)
attrib |= DBG_ATTRIB_PROPERTY;
if (m_fieldKind & FIELD_TYPE_CLASS)
attrib |= DBG_ATTRIB_CLASS;
if (m_fieldKind & FIELD_TYPE_INTERFACE)
attrib |= DBG_ATTRIB_INTERFACE;
if (m_fieldKind & FIELD_TYPE_INNERCLASS)
attrib |= DBG_ATTRIB_INNERCLASS;
if (m_fieldKind & FIELD_KIND_SYMBOL)
attrib |= DBG_ATTRIB_DATA;
//set the debug attributes
ppropertyInfo->dwAttrib = attrib;
}
return S_OK;
}
//////////////////////////////////////////////////////////////////////
// Helper functions
struct PrimitiveTypeInfo
{
LPCOLESTR pszName;
UINT size;
VARTYPE vt;
};
PrimitiveTypeInfo primitiveTypeTable[] =
{
{ OLE("string"), 0, VT_BSTR },
{ OLE("whole"), 1, VT_I1 },
{ OLE("whole"), 2, VT_I2 },
{ OLE("whole"), 4, VT_I4 },
{ OLE("whole"), 8, VT_I8 },
{ OLE("uwhole"), 1, VT_UI1 },
{ OLE("uwhole"), 2, VT_UI2 },
{ OLE("uwhole"), 4, VT_UI4 },
{ OLE("uwhole"), 8, VT_UI8 },
{ OLE("real"), 4, VT_R4 },
{ OLE("real"), 8, VT_R8 },
{ OLE("bool"), 1, VT_BOOL },
{ OLE("bool"), 2, VT_BOOL },
{ OLE("bool"), 4, VT_BOOL },
{ OLE("System.String"), 0, VT_BSTR },
{ OLE("System.SByte"), 1, VT_I1 },
{ OLE("System.Int16"), 2, VT_I2 },
{ OLE("System.Int32"), 4, VT_I4 },
{ OLE("System.Int64"), 8, VT_I8 },
{ OLE("System.Byte"), 1, VT_UI1 },
{ OLE("System.Char"), 1, VT_UI2 },
{ OLE("System.UInt16"), 2, VT_UI2 },
{ OLE("System.UInt32"), 4, VT_UI4 },
{ OLE("System.UInt64"), 8, VT_UI8 },
{ OLE("System.Single"), 4, VT_R4 },
{ OLE("System.Double"), 8, VT_R8 },
{ OLE("System.Boolean"), 1, VT_BOOL },
{ OLE("System.Boolean"), 2, VT_BOOL },
{ OLE("System.Boolean"), 4, VT_BOOL },
{ NULL, 0, VT_EMPTY }
};
HRESULT FieldGetType( in IDebugField* pfield, out VARIANT* pvarType )
{
HRESULT hr;
if (pfield == NULL)
return E_INVALIDARG;
if (pvarType == NULL)
return E_INVALIDARG;
else
*pvarType = 0;
//get type size and name
DWORD fieldTypeSize;
FIELD_INFO fieldTypeInfo;
IDebugField* pfieldType = NULL;
hr = pfield->GetType( &pfieldType );
if (FAILED(hr))
return hr;
hr = pfieldType->GetSize( &fieldTypeSize );
if (FAILED(hr))
{
pfieldType->Release();
return hr;
}
hr = pfieldType->GetInfo( FIF_NAME, &fieldTypeInfo );
if (FAILED(hr))
{
pfieldType->Release();
return hr;
}
//check for primitive types
memset( pvarType, 0, sizeof(*pvarType) );
VariantInit(pvarType);
for (PrimitiveTypeInfo* pprimTypeInfo = primitiveTypeTable;
pprimTypeInfo->pszName != NULL;
pprimTypeInfo++)
{
if (pprimTypeInfo->size == fieldTypeSize &&
(wcscmp(pprimTypeInfo->pszName,fieldTypeInfo.bstrName) == 0))
{
pvarType->vt = pprimTypeInfo->vt;
break;
}
}
//VT_UNKNOWN is used for all other (structured) types
if (pvarType->vt == VT_EMPTY)
{
pvarType->vt = VT_UNKNOWN;
pvarType->punkVal = pfieldType;
pvarType->punkVal->AddRef();
}
if (fieldTypeInfo.bstrName != NULL)
SysFreeString(fieldTypeInfo.bstrName);
pfieldType->Release();
return S_OK;
}
//----------------------------------------------------------------------------
HRESULT FieldGetValue( in IDebugField* pfield, out VARIANT* pvarValue )
{
if (pvarValue == NULL)
return E_INVALIDARG;
else
*pvarValue = 0;
if (pfield == NULL)
return E_INVALIDARG;
//we delay getting the primitive value by just setting VT_UNKNOWN
pvarValue->vt = VT_UNKNOWN;
pvarValue->punkVal = pfield;
pvarValue->punkVal->AddRef();
return S_OK;
}