如何使用RTTI将TDateTime属性与Double属性区分开？ [英] How can I distinguish TDateTime properties from Double properties with RTTI?

问题描述

在Delphi 2010中使用RTTI系统，有没有办法找出属性是否是TDateTime？当我回调为Variant时，如果我检查属性类型，它现在将其视为双精度。这是因为它只能看到基本类型吗？ （TDateTime = double）

Using the RTTI system in Delphi 2010, is there any way to find out if a property is a TDateTime? It's currently treating it as a double whenever I call back asVariant and also if I check the property type. Is this due to the fact it can only see the base type? (TDateTime = double)

推荐答案

尝试检查 Name TRttiProperty.PropertyType

Try checking the Name property of the TRttiProperty.PropertyType

我没有Delphi 2010，但这在XE中有效。

I don't have Delphi 2010, but this works in XE.

{$APPTYPE CONSOLE}

uses
  SysUtils,
  Classes,
  Rtti;

type
  TMyClass =class
  private
    FDate: TDateTime;
    FProp: Integer;
    FDate2: TDateTime;
    FDate1: TDateTime;
  public
   property Date1 : TDateTime read FDate1  Write FDate1;
   property Prop : Integer read FProp  Write FProp;
   property Date2 : TDateTime read FDate2  Write FDate2;
  end;

var
 ctx : TRttiContext;
 t :  TRttiType;
 p :  TRttiProperty;
begin
 ctx := TRttiContext.Create;
 try
   t := ctx.GetType(TMyClass.ClassInfo);
   for p in  t.GetProperties do
    if CompareText('TDateTime',p.PropertyType.Name)=0 then
     Writeln(Format('the property %s is %s',[p.Name,p.PropertyType.Name]));
 finally
   ctx.Free;
 end;
  Readln;
end.

此代码返回

the property Date1 is TDateTime
the property Date2 is TDateTime

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