Setting a "nullable" property on a .NET object
I have some .NET interop code where I've managed to load objects and read properties, however I am having trouble with setting a property on an object. Here's the relevant parts of the Delphi code:
uses
mscorlib_TLB, Winapi.ActiveX;
type
// Irrelevant parts of the code omitted
TDotNetObject = class(TObject)
private
FTarget: OleVariant;
FType: _Type;
public
procedure SetProperty(const APropertyName: string; const AValue: OleVariant; const AIndex: Integer = -1);
end;
function VariantToPSafeArray(const AValue: Variant): PSafeArray;
begin
Result := PSafeArray(VarArrayAsPSafeArray(AValue));
end;
procedure TDotNetObject.SetProperty(const APropertyName: string; const AValue: OleVariant; const AIndex: Integer = -1);
var
LPropertyInfo: _PropertyInfo;
LIndex: PSafeArray;
begin
if AIndex >= 0 then
LIndex := VariantToPSafeArray(VarArrayOf([AIndex]))
else
LIndex := nil;
LPropertyInfo := FType.GetProperty(APropertyName, BindingFlags_Instance or BindingFlags_Public or BindingFlags_NonPublic);
if LPropertyInfo <> nil then
LPropertyInfo.SetValue(FTarget, AValue, LIndex);
end;
procedure UpdateDefectStatus(const ADefectID, AStatus: Integer);
var
LObject: TDotNetObject;
begin
// ** Code to obtain the object omitted ***
LObject.SetProperty('Status', AStatus);
end;
An error is thrown when LPropertyInfo.SetValue is called in TDotNetObject.SetProperty:
The Status property type in C# is declared:
public enum DefectStatus
{
/// <summary>
/// Defect Reported.
/// </summary>
Reported,
/// <summary>
/// Defect assessed.
/// </summary>
Assessed,
/// <summary>
/// Defect on work order.
/// </summary>
OnWorkOrder,
/// <summary>
/// Defect closed.
/// </summary>
Closed
}
I found a solution for how to handle this situation using C# here:
https://stackoverflow.com/a/13270302/3164070
However I'm a bit lost as to how to do the same in Delphi. Any ideas?
https://stackoverflow.com/a/13270302/3164070
However I'm a bit lost as to how to do the same in Delphi. Any ideas?