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Get a list of variable names in a class at run time

I declared some simple classes in the program, for example

MyClass = class 
    Var1 : Integer
    Var2 : Integer
end;

What I would like to do is get a list of variables of this class ("MyClass") at runtime (maybe something like "GetPropList" for components?)

I mean something like this (obviously, the “GetVarNames” function does not exist, but I hope this gives an idea), which will pull the names of the variables listed in “MyClass” into strings in a TStringList:

var
    MyVariableNamesList: TStringList
    i : integer;

begin
    MyVariableNamesList := TStringList.create;        
    MyVariableNamesList := GetVarNames(MyClass)

end;

Can anyone advise? Sorry in advance if this is a stupid question!

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1 answer

Depending on your version of Delphi, you may use the new RTTI (introduced with Delphi 2010).

You can do something like this:

function GetVarNames(const AClass : TObject) : TStringList;
var lType : TRttiType;
  lContext : TRttiContext;
  lProperty : TRttiProperty;
  lField : TRttiField;
begin
  Result := TStringList.create;
  LType := lContext.GetType(AClass.ClassType);
  if assigned(LType) then
  begin
    for LProperty in LType.GetProperties do
    begin
      Result.Add(lProperty.Name);
      //Get current value:
      Result.Add(lProperty.GetValue(AClass).ToString);
    end;
   for lField in LType.GetFields do
   begin
     Result.Add(lField.Name);
     //Get current value:
     Result.Add(lField.GetValue(AClass).ToString);
   end;
 end;
end;
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