Cardinal 到 OleVariant 的错误转换。 UInt64 没问题

Question

program UInt32ToVariant;

uses
  Vcl.Dialogs, System.SysUtils, System.Variants;

var
  ui32Val: Cardinal;
  si64Val: Int64;
  ui64Val: UInt64;
  v1: Variant;
  v2: OleVariant;
  sb: TStringBuilder;

begin
  sb := TStringBuilder.Create();
  try
    ui32Val := 4234687430;
    si64Val := Int64.MaxValue;
    ui64Val := UInt64.MaxValue;

    v1 := ui32Val;
    v2 := ui32Val;
    sb.AppendLine('Unsigned 32 bit integer:'#9 + Cardinal.ToString(ui32Val));
    sb.AppendLine(#9'to Variant:'#9 + VarToStr(v1));
    sb.AppendLine(#9'to OleVariant:'#9 + VarToStr(v2));
    sb.AppendLine();

    v1 := si64Val;
    v2 := si64Val;
    sb.AppendLine('Signed 64 bit integer:'#9 + Int64.ToString(si64Val));
    sb.AppendLine(#9'to Variant:'#9 + VarToStr(v1));
    sb.AppendLine(#9'to OleVariant:'#9 + VarToStr(v2));
    sb.AppendLine();

    v1 := ui64Val;
    v2 := ui64Val;
    sb.AppendLine('Unsigned 64 bit integer:'#9 + UInt64.ToString(ui64Val));
    sb.AppendLine(#9'to Variant:'#9 + VarToStr(v1));
    sb.AppendLine(#9'to OleVariant:'#9 + VarToStr(v2));

    ShowMessage(sb.ToString());
  finally
    sb.Free();
  end;
end.

结果是：

Unsigned 32 bit integer:    4234687430
    to Variant: 4234687430
    to OleVariant:  -60279866 (Wrong!)

Signed 64 bit integer:  9223372036854775807
    to Variant: 9223372036854775807
    to OleVariant:  9223372036854775807

Unsigned 64 bit integer:    18446744073709551615
    to Variant: 18446744073709551615
    to OleVariant:  18446744073709551615 (Correct again!)

这真的是 Delphi 中的错误还是我做错了什么？

我可以假设 OleVariant 根本不支持无符号整数，但支持无符号 64 位整数，不支持 32 位。

Answer 1

这是一个 Delphi 错误。

报告为RSP-18363 Incorrect Conversion Cardinal to OleVariant

错误描述：

Incorrect direct conversion of the Cardinal to OleVariant. The result differs from the transformation of the Cardinal into the Variant into the OleVariant

Cardinal 到 OleVariant 的错误转换。 UInt64 没问题

Erroneous conversion of Cardinal to OleVariant. UInt64 is ok

delphi

types

variant

unsigned-integer