How do I use RTTI to set an enumerated field's value ?
I.e.
type
TCPIFileStatus= (fsUnknown, fsProcessed);
TTest = class
FStatus: TCPIFileStatus;
end;
...
var
Data: TTest;
Ctx: TRttiContext;
Status : TCPIFileStatus;
begin
Data := TTest.Create;
Status := fsProcessed;
Ctx.GetType(Data.ClassType).GetField('FStatus').SetValue(Data, Status);
end;
I get "Invalid class typecast."
NB:I need to use RTTI because I will not always know the object type or field name at design time.
you must pass a TValue
to the SetValue
method try using this code :
{$APPTYPE CONSOLE}
uses
Rtti,
SysUtils;
type
TCPIFileStatus= (fsUnknown, fsProcessed);
TTest = class
FStatus: TCPIFileStatus;
end;
var
Data : TTest;
Ctx : TRttiContext;
Status : TCPIFileStatus;
v : TValue;
begin
try
Data := TTest.Create;
try
Status := fsProcessed;
v:= v.From(status);
Ctx.GetType(Data.ClassType).GetField('FStatus').SetValue(Data, v);
// do your stuff
finally
Data.Free;
end;
except
on E: Exception do
Writeln(E.ClassName, ': ', E.Message);
end;
end.