8
uses
SysUtils, Variants;
var
VariantSingle: Variant;
VTSingle: TVarType;
SingleTest: Single;
VariantDouble: Variant;
DoubleTest: Double;
VTDouble: TVarType;
begin
SingleTest := 1.234;
VariantSingle := SingleTest;
VTSingle := VarType(VariantSingle) and varTypeMask;
DoubleTest := 1.23456;
VariantDouble := DoubleTest;
VTDouble := VarType(VariantDouble) and varTypeMask;
WriteLn(Format('VarType: Single: %d, Double %d', [VTSingle, VTDouble]));
end.
上面会输出代码:为什么将单个变量分配给VarDouble变体会导致varDouble变体?
VARTYPE:单:5,双5
从System.pas
varSingle = $0004; { vt_r4 4 }
varDouble = $0005; { vt_r8 5 }
因此,我期望VTSingle到是 - 不是5
我错过了什么?
你是否将'_VarFromReal'程序从asm翻译成了Pascal?至少在Delphi 2009中,它是作为一个'asm'程序来实现的。 – 2013-02-28 11:11:15
@AndreasRejbrand现代Delphis还拥有Pascal版本,以利于新的非x86目标。所以我在这里使用了Pascal版本。 – 2013-02-28 11:13:36